101101An Introductory Courseon the Basics of Ceramics

Presented by Mayco

CeramicsCeramics

Table of Contents

Health & Safety 1

Clay 3

Kiln Firing & Operation 7

Underglazes 14

Glazes 17

Problems, Causes & Solutions 21

Glossary 26

Quick Reference Guide 33

A Word from Mayco...

This booklet is designed to give you a general overview of the ceramics process. We have outlined therecommended use and application for products, but keep in mind that this is a guideline; often you can achievesuccessful results by breaking the rules. Ceramics 101 is meant as a starting point so you will know how andwhen to bend the rules to fit your needs.

Mayco has been manufacturing high quality ceramic products for over 50 years. Our products areenjoyed by different ceramic enthusiasts all-around the world: hobbyists, potters, educators, contemporary studiosand finished-ware producers.

We work very hard to provide you with consistent, top performing glazes in a broad range of color in bothnon-toxic and health caution formulas. Our engineers have established very strict quality control procedures toensure that the product you receive performs to the very highest standards. All products are tested by anindependent toxicologist and are properly labeled for conformance to ASTM and FDA guidelines.

This guide is designed to provide you with basic information on how the ceramic process works. Formore in-depth product usage information, see our publication, The Mayco Book, for a complete reference on all ofMayco’s high quality products. Of course, our technical service and education departments are available to workwith you to achieve better understanding, maximizing the performance of our products. For any questions, pleasecontact us at 614-876-1171 or email your questions to technical@maycocolors.com.

4077 Weaver Court South • Hilliard, Ohio • 43026614-876-1171 • Fax: 614-876-9904

www.maycocolors.com • info@maycocolors.com

Ceramics is one of the most rewarding and enjoyable ofall hobbies, and one of the safest, if some simple common-sense precautions are taken. As with any activity, responsi-bility must be taken for safe practices.

General rules of good housekeeping and common senseshould be applied when doing ceramics. Following simplerules will ensure your safety and help you produce greatresults when creating a ceramic project.

Our “Health and Safety Bulletin” is available for thatpurpose. It is available on our web site at www.mayco-colors.com. In addition to this bulletin, we urge you to readother health and safety information, and to talk to yourdealer, distributor or certified ceramics teachers about thesafe use of ceramic products. MSDS (Material Safety DataSheets) are available on our website or can be obtained bycontacting Mayco Customer Service Department.

All Mayco products are properly labeled for materialsafety. Read labels with care. In ceramics, as in all areas ofhuman activity, proper usage of products ensures safety. It isthe responsibility of the user to read and understand theproduct label and to follow the guidelines for safety. Anyonenot able to understand and follow the label instructions andsafety guidelines should have an adult, competent of doingso, supervising the application and usage of all Maycoproducts. This includes the preparation, application andfiring of these products. The person firing a kiln shouldhave complete knowledge of and understand the specificinstructions for operation of the kiln as provided by themanufacturer. The user should know any local ordinancesapplicable to the installation of the kiln.

To ensure your health and safety, follow these simplerules:• Keep work surfaces and shelves clean by wiping down

with a wet sponge.• Clean up spills when they occur. Do not allow to dry.

Keep dust under control at all times.• Work on a newspaper or paper towel for easy clean up and

disposal.• Do not smoke, eat or drink when working with hazardous

ceramic materials. Do not put your brush or brushhandle in your mouth.

• Wash your hands before you begin. The natural body oilsand salts on your hands may affect the finished piece. Anyopen cuts should be properly covered.

• Wash your hands thoroughly when you are through working.• Use a smock when working with ceramic materials. Wash

often and separately from other garments.• Keep children away from kilns and out of glaze dipping

rooms. Only a qualified adult should operate a kiln.• Children should not use lead-containing glazes or other

hazardous ceramic materials.• Do not intermix dinnerware safe glazes containing lead.• If pregnant or contemplating pregnancy, tell your physician

about your work with ceramics.

• When using solvent-containing ceramic materials, work outdoors, in a locally exhausting hood or with an exhaust fan.Do not use or store near kilns, other heat sources or an openflame. Dispose of used rags in an airtight metal container.

• Do not spray apply any product.• Do not fire kilns in an enclosed area. Use a kiln ventilation

system. Carbon monoxide fumes can build up and presenta danger. Consult with your kiln supplier or manufacturerfor more information.

• If you should ingest ceramic products, seek medical helpimmediately.

A neat work area should include the following:• A table covered with several layers of newsprint and a

comfortable chair. • An old towel under the newsprint - this will cushion the ware.• Only the products and pieces that you are working with at

one time to avoid contaminating other pieces.• Proper ventilation.

The labels on a product are very important and give youa wealth of information. Read the label for information onproper product use and hazards, if any.

Ceramic glazes are manufactured using a variety of rawmaterials. Most of the ingredients are mined and extractedfrom the ground. Some of these materials can be classifiedas toxic and if misused can be harmful. The key to safe useof all art materials starts with professional education andtraining. Contact your Mayco distributor for information onseminars in your area.

Non-Toxic GlazesNon-Toxic glazes are formulated without the addition of

lead. They are tested for safety by an independent toxicol-ogist. They meet FDA standards and those for the Arts andCraft Material Institute for which the non-toxic seal isassigned. You can use these glazes and products with confi-dence and ease. These products contain no materials in suffi-cient quantities to be toxic or injurious to humans or to causeacute or chronic health problems. This does not mean thatany less care should be given while handling these products.

Dinnerware Safe (Food-Safe) Glazes Many glazes are formulated to be safely used on surfaces

that come into contact with food or drink. • If surfaces will come into contact with food or drink, use

only glazes that are labeled food or dinnerware safe.Follow label instructions closely.

• Do not mix lead-containing dinnerware safe glazes, as thebalance of ingredients in each glaze will be disrupted.Each mixture would have to be re-tested by an approvedlaboratory to determine if the mixture is also food safe.

• It is the responsibility of anyone making pieces for resaleto have them tested by an approved laboratory for leadrelease.

Health & SafetyPreparation, Application and Firing

1

• Proper firing of dinnerware safe glazes is critical. Use shelfcones on the kiln shelves to ensure that the pieces are fired hotenough, even if the kiln is electronically controlled or has anautomatic kiln sitter. Always fire in accordance with manufac-turer’s instructions. If crazed or under fired, these glazes maynot be food safe. Too heavy an application of glaze, fastfiring or not firing to the proper shelf cone listed on the labelmay result in a glaze that does not meet the FDA standards.

Lead and/or Cadmium ContainingGlazes

Lead and cadmium are used in many ceramic glazes.Cadmium is used to produce brilliant reds and yellows. Leadgives a brilliance to the glaze and allows the glazes to maturewell at lower firing temperatures (shelf cone 06).

Glazes containing lead and/or cadmium should be handledwith respect. The dust from such glazes should not be inhaled.Anyone who is pregnant or contemplating pregnancy shouldonly use these glazes with professional supervision. Use goodpersonal hygiene when working with these types of glazes andkeep them out of the reach of children.

Sprays, Solvents and Overglazes These products are easy to use safely and will present no

problems as long as these important rules are observed: • Containers should be kept tightly closed when not in use.• Keep out of reach of children.• Aerosol sprays, solvents and solvent-based overglazes should

be used outdoors, with a locally exhausting hood or spraybooth or a window exhaust to assure adequate ventilation.

• Do not use near an open flame or heat source.• Clean up after use and dispose of products properly in a

metal container designed for disposal of flammablematerials. Contaminated materials can be washed or placedunder water until final disposal.

SlipThe mixture of any fine powder like slip requires the use

of a safety mask approved by OSHA. The work area shouldbe well ventilated with a system that draws all dust. Thisarea should be away from other working areas so as not tospread the fine dust particles. Good housecleaning habits arenecessary when mixing and pouring slip. Wipe up spillsimmediately. Do not sweep the area. Chronic lung damagemay result from prolonged inhalation and exposure to theclay dust.

Labeling InformationThe labels on a product are very important and give you awealth of knowledge. Read and understand the label forproduct’s use and hazards, if any. Ceramic hobby glazes aremanufactured with a variety of raw materials that are minedand extracted from the ground. Some of these materials canbe classified as toxic and if misused can be dangerous. Thekey to safe use of all art materials starts with professionaleducation and training. Location of information on labelsmay vary slightly due to space limitations.

2

Health & Safety

Toxicity StatusContentsApplication/Firing

InstructionsSpanish

instructions

Cone 6 Results Product Lot #

Product Family

Product Number

Color NameMayco Address/

European Address

Toxicity Status

ContentsApplication/FiringInstructions

Cone 6 Results Product Lot #

Product Family

Health Warnings Product Number

Color Name Mayco Address/European Address

Clay is a compound of minerals and organic materialresulting from the natural decomposition of certain igneousrocks (for example, feldspar and granite are two commonsources of clay minerals). As these mineral deposits age andget moved around by natural forces (wind, water, glaciers),chemical changes occur which cause the materials to becomeclay.

The two major classes of naturally occurring claydeposits are primary clays and secondary clays. Primaryclays are those that remain at the physical location where theparent rock decomposed. These clays tend to be the mostpure, but tend to be less plastic than secondary clays.Secondary clays are deposits that have been transported bywind, water, or glacial activity. These clays, while still verypure, generally have had other materials introduced into theirbasic composition that change their performance character-istics (color, plasticity, etc.)

Types of ClayClays can be grouped or classified several ways:

according to the way they are found in nature, by theirphysical and chemical properties, by the way they are used tomake finished properties, and so on. One of the first ways toclassify clay is by the methods used by Mother Nature tocreate clay deposits. The major types of naturally occurringclay are as follows:

Kaolin or China ClayChemically known as Al2O3-2SiO2-2H2O this clay is

almost pure white as a primary clay and slightly less whitebut more plastic as a secondary clay. These clays are a majorcomponent of most high-fire porcelain clay bodies and arefrequently used in stoneware to lighten the fired color.

Ball ClayThese are secondary clays that have been transported to

swampy areas where organic acids have broken down themineral particles to ultra fine size. These clays are extremelyplastic – if used alone they will shrink quite a bit, causingsevere cracking.

Earthenware Clay Earthenware is the most common surface clay found

throughout the world. These clays usually contain highamounts of iron, which gives the fired wares the character-istic terra cotta color. True earthenware clay cannot vitrify,which means the clay body remains porous after firing.

Stoneware Clay Stoneware tends to be kaolins that contain more

impurities - usually calcium, feldspar, and iron - resulting inclays that have finer particle sizes and higher flux content.The flux materials cause the clay to vitrify at lower firingtemperatures.

Fire Clay Similar to stoneware clays, fire clays generally contain

less flux (especially calcium and feldspar). Fired alone theseclays won’t fully vitrify – even at high fire temperatures.

Bentonite ClayBentonite is formed from the decomposition of volcanic

ash. Bentonite has the finest particle size of any natural clay.It is very useful as a plasticizer but it must be used in moder-ation – too much of it in a clay body will result in crackingduring the drying process.

Slip ClayThese are naturally occurring clays that have a high iron

content. At high temperatures these clays melt to form aglaze; no additives needed.

Pure natural clays almost always have shortcomings – ina potter’s eyes. The production processes and ultimate use ofthe piece dictates the properties the clay needs to have –either during the forming stage or as a finished piece. A claybody is a mixture of clay and other materials designed tomeet the needs of the user. Design objectives for a clay bodymay involve making it more plastic during the throwingstage, improving the body’s stability in large-scale work,helping the body resist thermal shock from firing, andimproving general properties such as vitrification and density.

The “other materials” in a clay body perform a specificfunction to make the final product work better for the clayuser. A general description of each component and itspurpose are discussed below.

Components of a Clay BodyAll clay bodies involve combining clay (many recipes

call for several types of clay) with non-clay additives. Thebasic types of additives and the purpose for each are asfollows:

Flux These materials act as melting agents, helping to lower

the maturing temperature and assist in the formation of glass- the essential binder in all ceramics. Some clay containshigher concentrations of fluxes naturally–feldspar and ironare the most common.

Glass-FormersThese materials react with fluxes to form glass. The

most common glass-former is silica. Pure silica melts at veryhigh temperatures – the proper mix of flux materials andsilica allows for glass to be formed at more manageabletemperatures. This balance must be carefully achieved – toomuch flux produces a weak glass, too much silica can lead toreduced thermal shock resistance.

RefractoriesThese materials stabilize the body, providing the physical

What is Clay?Clay & Clay Bodies

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structure or binding material for the flux and glass-formers tobind together. The primary refractory material is alumina.Rather than add pure alumina high alumina clays, such as fireclay or kaolin, are blended into the clay body to increase thealumina content.

FillersThese gritty, granular materials that improve a clay body

by enhancing the forming strength, decreasing shrinkage,provide for more even drying and greater thermal shockresistance. A common filler material is grog – a materialformed by grinding previously fired clay into a sandy grit.

PlasticizersOccasionally a clay body will need accessory plasticizers

to improve the moldability and flexibility of the clay. Certainporcelain bodies and pure kaolins benefit from additives suchas bentonite, Veegum T, or macaloid.

The combination and proportion of these ingredients willaffect the general properties of the clay – how it will behaveprior to firing and perform after firing.

Clay Materials PropertiesIt is a common practice of materials scientists to classify

and evaluate materials by the properties the material containsor exhibits when manipulated and used. Every material canbe evaluated by objective criteria, such as chemical, electrical,physical characteristics and behaviors.

There are two fundamental properties that really defines aclay: its ability to be molded and shaped and how it fires.Some clays are more flexible, or plastic, than others, some canbe fired to high temperatures while others cannot. Otherattributes one may consider include color (of the clay bodyitself), porosity, vitrification (firing characteristics), glaze fit,shrinkage, maturing temperature, and so on. Some of theterms and concepts used to describe clay follow:

Plasticity Refers to the ability of a clay to be molded and shaped.

There are several factors that affect clay’s plasticity: mineralparticle size, acidity levels, amount of water, amount of nonplastic additives, etc. The state of clay particles “stickingtogether” or “separating” has a technical, chemical expla-nation. Rather than digress into a scientific discussion onpositive or negatively charged particles let’s just come tounderstand these opposite processes as follows:

FlocculationThe process of adding an acidic substance which causes

clay particles and minerals to attract one another (flocktogether). This process increases the stickiness or plasticity ofa clay body.

DeflocculationThe process of adding an alkaline substance to a clay

mixture that causes the particles to repel one another. Whilenot commonly added to clay compounds deflocculants areused to help liquefied clay (slip) stay in suspension and flow

better.Vitrification

The process under which the clay body experienceschemical and physical changes during firing. The changesthat take place during firing take place in stages. During thefirst firing stage the clay is fired to a red heat and the particlesare now stuck together permanently - but the glass-formingprocesses have yet to begin. The clay body is said to besintered. A sintered body is considered fired – it has nowbecome bisque. Bisque bodies have strength – not has muchas a vitrified body – and are very porous. At this stage theclay can no longer be slaked down (reconditioning dry clay toa more moist state by adding water). For some clay bodiesthis stage IS the final stage of firing. Earthenware, forexample, matures at low temperatures and does not vitrify.Earthenware clays remain porous when bisque fired, requiringglazing to make a waterproof surface.

As temperatures climb past the sintering stage the fluxesand glass-formers begin to interact - the particles actually fusetogether, forming glass between and around the mineralparticles. The glassy materials strengthen the sintered connec-tions between the refractory particles and gradually consumethe air spaces in the clay body. When almost all the air spacesare filled and the glass-forming stage is complete the body issaid to be vitrified. A vitrified body is impervious to water,very strong and dense (a vitrified body shrinks and condensesas the air spaces are filled with glassy material).

Each clay body has a maximum firing range whose toptemperature, if exceeded, will result in deformations.Bloating, warping, slumping, or complete loss of structure arethe physical signs of an overfired body.

Porosity Porosity refers to a material’s ability to absorb moisture

(absorption is the common term used by clay users). Porositycan easily be measured by weighing a mature fired butunglazed piece of clay or clay body, then place the sample in apan of water, bring to a boil, let cool overnight. Blot off theexcess water and weigh again. The percentage increase inweight represents the porosity of the clay. Earthenwaretypically has an absorption rate of 5% to 14%, stoneware 2%to 6%, and porcelain 1% to 3%.

Shrinkage Shrinkage occurs in all clay bodies as they are dried and

fired. Considerable shrinkage occurs as water evaporatesfrom the wet greenware stage to the bone-dry greenwarestage. The more plastic the clay body, the greater the dryingshrinkage. A typical shrinkage rate for wet greenware isbetween 4% and 10%. Shrinkage from the firing of a claybody in a large part depends on the flux content and size andquantity of refractory materials. A pure kaolin clay or claybody can shrink as much as 8% during firing, whereasrefractory bodies may have extremely low shrinkage. Theaddition of grog material can greater aid in reducing theshrinkage due to firing of a clay body. Grog is finely groundup bisque added to the clay to reduce the shrinkage or forthermal shock.

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Clay

Classifications of Clay BodiesTwo common methods of classifying clay bodies are

according to the firing temperature range of the clay and bycomposition.

Pyrometric ConesThe evolution and history behind the development of

pyrometric cones is interesting – any practitioner of ceramicsor pottery should be well acquainted with their purpose.Perhaps the best resource on pyrometric cones in the U.S.would be the Orton Ceramic Foundation(www.ortonceramic.com). A non-profit organization dedicatedto the ceramic industry Orton publishes many handbooks andguides on proper firing and kiln operation. Their publication,“Cones and Firing” is a mandatory read and reference forevery clay user. A brief overview of cones is all that is neededat this time.

A pyrometric cone is a small pyramidal-shaped compo-sition of clay, frit and binders that bend at a specific temper-ature. They are the standard method for determining thematuring temperature of a clay body. Just like the clay bodiesthey monitor, cones respond to temperature, duration, andatmosphere. As the firing progresses and reaches maturity thetips of the cones begin to bend down, forming an arch. Whenthe tip of the firing cone reaches the bottom of the cone thefiring is complete.

The lowest cone number is a cone 022 which “bends” ataround 1080∞ F, while the “hottest” cone is a cone 42 – a coneused in advanced ceramic industry and a temperature you’llnever want to experience.

Clay and glazes are commonly classified according to theirfiring range. Low-fire clays mature between cones 010 and 06– referred to as the bisque-fire range; mid-range clays maturefrom cone 4 to cone 7; high-fire clays mature at cone 8 to cone11 – occasionally higher.

Clay Body CompositionsEarthenware – traditionally red or buff colored, these clays

are rich in iron. To offset the flux properties of the iron a goodearthenware body will include fair amounts of grog or sand –to give the body structure – and fireclay or stoneware to helpimprove the body’s ability to take higher temperatures withoutbloating or deforming.

Another type of earthenware clay body that is more“designed” than found in nature is the whiteware body. Thesebodies general exclude the use of natural earthenware clays andare comprised of talc and ball clays. These clay bodies areoften white (hence the name) and are popularly used fordinnerware.

PorcelainPorcelain is most commonly known for their whiteness

and for having some degree of translucency. They are pureand vitreous, which gives them their inherent glaze, fit quality,hardness, and durability. The whitest porcelains usually featureup to 50% kaolin as the primary clay component with additivessuch as bentonite or macaloid to help improve plasticity.

True bone china is so titled due to the addition of bone ash

(calcium phosphate). The calcium reacts with silica to developa very glassy material, giving the finished product the tradi-tional translucent look.

StonewareThese clay bodies use natural stoneware clay and/or

fireclay, with ball clay, kaolins, flint, fluxes and grog or sand asadditives. The choice of additives is truly an issue of materialdesign and use. For example, adding sand or grog gives morestructure reduces slumping. Clay users who want to hand buildor throw taller wares with thinner bodies may opt for this typeof body. Silica and feldspar may be added to help control thematuring temperature and glass-forming characteristics of thebody.

Stoneware clay bodies produce durable ware and generallyreact favorably to the kiln environment during reduction firings(reducing or restricting the amount of oxygen in the kiln, whichcauses carbon and hydrogen to build up inside the kiln, alteringthe appearance of the clay and glazes used in such a firing).

Refractory These clay bodies are used for making firebrick and kiln

furniture (A refractory material is one that can withstand hightemperatures). A hot-face fire brick might include up to 80%grog and 20% plastic fireclay or low-iron ball clay. Whilethere are many types of refractory applications, the highertemperature bodies will require reduced amounts of flux.

*The above information was compiled from “Clay: A Studio Handbook” by Vince Pitelka.

Determining Which Clay is Best for YouWhen looking for clay, compare the temperature range

used for the glaze. For example, if using Mayco’s Series 2000,which is 06-04 glaze, look for an 06-04 clay body, which isEarthenware clay. This will ensure the best glaze fit.

Suggested Clay Bodies for TeachersWhile any earthenware clay is ideal for teachers, white

earthenware is the most time-efficient clay to use - sinceteachers do not have the time to fire long. Although redclay gives beautiful results, many teachers do not like ironin their classrooms or on students’ clothing.

It is easier to achieve bright glaze colors with whiteearthenware. This clay body will work for all grades andprojects. A slight addition of grog can be helpful to aid incrack problems and the capacity of the clay to take on avariety of forms.

While earthenware clay is suggested, it is important toremember that they do not totally seal or become imper-vious to water. Earthenware clay absorbs moisture evenafter fired to temperature and is not weatherproof or frost-proof. When left outside and exposed to extreme tempera-tures and weather conditions, glazes applied to Earthenwareclays can craze and crackle. If someone is looking for weatherproof clay, stoneware orporcelain clay are better choices as the body is vitrified afterfiring. These clays are typically fired to cone 6 or higher.They can be used outdoors and for functional uses.

5

Clay

Storing and Reprocessing ClayIt is necessary to store clay in a sealed plastic container.

Purchase some large plastic bins. When doing a project youwish to return to later, store the project in the bins to keepthem damp and organized by class. If the projects seem to dryout, damp paper towels or a damp sponge can be placed in thebin and will help keep projects moist.

Teachers often have left over clay or inherit clay from aprevious teacher or program. Clay left over from a project cansometimes get a little too dry, but doesn’t need a total repro-cessing effort. Divide the clay into pieces no larger than a golf

ball (students can assist with thisprocess) and use a mistbottle to moisten the claywhen it is put into the bag.Seal the bag and it will beready for the next day,although it will stay softlonger than normal. If clayis too wet, pull off bag andexpose to air for appropriateamount of time. Determineappropriate amount of timeby evaluating room temper-ature, humidity, etc.

If a block of clay hasgotten too dry it does notwork to dump water into thebag. This will only make the

outside slimy and not penetrate the interior of the block.Instead, use one of these two ways:

• If the clay is firm, but not totally dry, unbag it. Cut it into quarters using a wire. Wrap these blocks with a very damp to wet terrycloth towel. Rebag it and set aside for a day or two. It can be left longer, but may get moldy if left for an extended period of time.

• Unbag the clay and cut into thick slices (approximately 1 1/2” – 2”) thick. Use your finger (or if too firm, something similar in size) to poke deep holes without going through the bottom. Fill these recessions with water, stack and rebag. This needs to sit for at least overnight.

If clay is totally hard or bone dry it will need to becompletely reprocessed. Bone-dry clay reprocesses faster andmore evenly than leather hard clay. You can always get astudent to help break up this piece of dry clay. To reprocess:

• Get a large trash can and add clay. Cover with water. Let this sit for a few days, if possible. Dig the clay out in large handfuls, letting water drain. Place on a dry plaster slab approximately 2” thick. If you don’t have a slab, use a thick piece of wood. These materials will absorb water from the clay. When it is the consistency you desire, remove it and place in plastic bags. This clay may take some kneading before or after it is bagged to prepare for projects.

*The above information was compiled from Kathy Skaggs at AtlanticBeach Pottery and Craig Freiburger at Armadillo Clay.

6

Clay

Dry Cleaninggarment bags are a

good source forwrapping clay in and

protected projectsfrom drying out.

Students can bring indiscarded laundrybags from parents.

Unusual Ideas for Creating TextureWhen creating a clay piece there are

several items you can use to createtexture. Once you start brainstorming,the ideas are endless. Some uniqueitems, many of which you will findaround the house, are:• Tire Treads• Burlap cloth

• Paper towels• leaves, branches• meat tenderizer• garlic press• rubber stamps• cookie cutters

• lace or doilies• bubble wrap• jello molds

• waffle iron • crinkle cutter (for vegetables)• corn cob (with hard kernels)

• wood • brush•comb

• whisk• toothbrush• rocks• dough cutter• sponge• beads• decorated silverware handles • scouring pads• screen

GetCreative!The possibilities

are endless!

Many kiln operators feel that opening the kiln after thefiring is more exciting than Christmas morning. However,firing is as big of a responsibility as it is a pleasure. It is themost essential step the ceramist has in producing thefinished “objets d'art.”

Successful kiln firing requires knowledge and under-standing of the equipment, what happens in the kiln duringfiring, and the various reactions of the different items andmaterials placed into the kiln. Learning these necessary funda-mentals are easily obtained with reading and first handexperience of the kiln. First of all, read and understand the kilnmanual. If you do not have one, write to the manufacturer andthey will send the materials needed to operate your kiln.

There are several types of kilns available. Basically,kilns are specially designed ovens used for firing (baking)ceramic objects to a very high temperature. This ovenconverts the raw materials into ceramics by subjecting themto high temperatures. While the electric kiln is mostcommonly used kiln, there are also other types of kilnsfueled by oil and gas. The gas and oil are the leastpractical, due to their fuel source and their interaction withthe types of glazes used with whiteware.

Kiln installation should be done by a qualifiedelectrician. Check with your electric company for peakpower demands that can affect your firing. If fuses orcircuit breakers trip during firing, lower amounts of voltagewill go to the kiln, causing the kiln to perform incorrectly.The location of the kiln should:

• Be on level concrete flooring or an asbestos pad.• Be located in a well vented room.• Be located in a protected area, away from foot traffic.• Allow easy access to the kiln opening, controls and

peepholes.• Be near the correct electrical outlet. Check the

manufacturer’s requirements for voltage needs.• Do not allow the pigtail cord or power supply cable to

rest on the side of the kiln.

Pyrometric ConesThe kiln operates using degrees of heat more

commonly referred to as cone numbers. There are severaltypes of cones and numbering systems for ceramicsthroughout the world. The one most accepted in ceramicsis the Orton cone, determined at the National Bureau ofStandards. There are other types and standards that may beapplicable in countries other than the United States.

The pyrometric cone is a small elongated triangularpyramid composed of clay and other materials. Thesecones are a self deforming ceramic piece, that whensubjected to heat and time, signal the kiln sitter (see belowabout kiln sitter) that the kiln has done the necessary work.When the cone has deformed to its specifications, theobjects in the kiln have reached the equivalent of theneeded temperature and length of time to mature theproducts used.

Cones are a necessary, vital tool in ceramics, signalingthe user that time and temperature have been obtained.While an extremely slow firing or fast firing can fool thecone into deforming at a different temperature, cones arestill a very important part to the success you have creatingbeautiful pieces.

Fast FiringsFast firings or rapidly increased temperatures should be

avoided. The rate of temperature should be approximately250˚ to 350˚ per hour. The temperature rate should neverexceed 500˚ per hour. Most automatic kilns are in the 350˚ to400˚ rate per hour range. This is important factor for you toknow. Too fast of a firing will not allow the piece or theglazes to mature. The result will be lackluster color, chalkysurface or immature bisque that can cause problems later infiring. Although a cupcake can be cooked within minutes ofputting it into the oven, a fruitcake will take several times thatto fully cook; a hotter oven would simply burn the outsideand leave the inside uncooked. The same applies toceramics.

Types of ConesThere are two types of cones: small cones (1 1⁄8 inch) are

used in the Dawson Kiln Sitter (see page 8 for explanation ofkiln sitters) that allow the kiln to shut off when the ware hasmatured. This can be a triangular pyramid or a bar. The largecones (2 1⁄2 inch) are called shelf or witness cones. These twotypes of cones are not interchangeable in their usage; eachhas special needs in order for them to perform as designed.

Shelf or Witness Cones The large cone commonly referred to as the shelf cone

(or witness cone) is the back-up system to the kiln sitter.These cones are placed throughout the kiln during firing toshow what is happening during your firings.

Check the cones when they are broken apart from oneanother. If there is a hollow spine on the cone, do not useit; the cone will deform incorrectly during the firing, givingyou a misreading. Shelf cones can be self-supporting orheld in place with some form of holder, as long as they areat an 8 degree angle. The self-supporting cones eliminateany error of a wrong angle. Ideally cones should be placedin the middle of the kiln shelves with a clear visual path tothe peepholes and to the element behind the cone for easeof viewing during the yellow-hot temperatures. Even if theideal is not obtainable, shelf cones should be placedthroughout the kiln on shelves out of a draft and threeinches from the kiln elements. Shelf cones are used in a series of three:

• The Guide Cone is one cone cooler than the desiredfiring temperature.

• The Firing Cone is the cone temperature you wish toachieve.

• The Guard Cone is one cone hotter than the desired cone.

All Fired Up . . .Kiln Firing and Operation

7

Shelf cones enable you to get to know the personality ofyour kiln. Yes, they do have one, believe it or not. A goodcook knows that their oven performs with different character-istics, as does your kiln. As the kiln fires, there may be areasof the kiln significantly cooler or hotter, affecting the outcomeof your fired pieces. It is highly recommended that shelfcones be used with every firing and at various placements onshelves to develop a graphic picture to the heating peculiaritiesof your kiln. Keeping a record of firing times, cone placementand degree of deformation can alleviate many heartachesdown the road. These records will help you make adjustmentsto the firing process. A half cone difference throughout thekiln chamber is considered very good.

Cone Numbering System Relative toTemperatures

Cone manufacturers produce firing cones for everyconceivable heat treatment involving maturing clays andglazes. The chart that follows lists the cones and the temper-ature where, under specified conditions, they would bend.The numbering system may appear confusing, but it issimilar to a thermometer. Increasing numbers above animaginary zero cone represent higher temperatures, whileincreasingly minus numbers below zero represents lowertemperatures. Minus numbers (and lower temperatures) areindicated by "0" preceding the number. For example, Cone06 is lower (cooler) than Cone 05. The zero is veryimportant when reading and following firing directions forthe materials used.

Shelf cones numbered the same as the small cones usedin the sitter are designed to deform and mature at a givendegree of heat. They are not interchangeable in use for theshelf or sitter. The smaller cones can not be used as a shelfcone because they require a hotter temperature to deform.Smaller cones would give inaccurate indication of the kiln

firing. Concurrently, a large shelf cone forced into the sitterwould damage the mechanism.

Kiln SitterThe W.P. Dawson Kiln Sitter is the control for the kiln and

is the most widely used one today. There are newer types ofkilns with computer controls that will be discussed later. Wehighly recommend installing a sitter on you kiln for it enablesyou to have more consistent firings with less chance ofmisfirings.

Place a small cone in the cone supports and the sensingrod, as illustrated in View A. Try to center the cone in thesitter, for it can make a few degrees difference in the firing.The sitter is activated at the beginning of firing manually,outside of the kiln (View B), and turned off by the deformationof the small pyrometric cone on the inside of the kiln (View C).Do not jar the kiln sitter and tube assembly during loading orfiring; it could result in overfiring or misfiring of the kiln.

Make sure to keep your kiln sitter clean. The conesupports and porcelain tube assembly should be vacuumedbefore the first firing and periodically with use. If a pieceexplodes during firing, thoroughly clean and vacuum the tubeassembly and the whole kiln (walls, floor and elements) beforethe next firing.

GuideCone

FiringCone

GuardCone

8

Firing

GuideCone

Correct Deformation After Firing

FiringCone

GuardCone

Cone Numbering SystemCone # 108˚ F* 270˚F+ Kiln Color Ware Type++

10 2345 2381 White Commercial9 2300 2336 Porcelain8 2257 23057 2219 22646 2194 2232 Hobby Porcelain5 2151 2185 & Stoneware4 2134 21673 2106 21342 2088 2124 High Fire Glaze1 2077 2109 Semi-Vitreous01 2043 2079 Ware02 2014 2048 Yellow03 1987 201404 1922 1940 Earthenware05 1888 191506 1816 1830 Low Fire Glazes07 1783 180308 1733 1751 Orange09 1679 1693010 1629 1641011 1627 1641012 1591 1623013 1586 1566 Cherry Red014 1533 1540 Semi-Melting Glass015 1454 1479 (Bottle Sagging)016 1407 1458017 1341 1377 Decals018 1285 1323 Metallics, 019 1234 1261 China Paint & Lusters020 1157 1175 Dull Red021 1116 1137 Glass Colors022 1085 1112 Glass Decals

* If rate of heat increase is 108ºF per hour.+ If rate of heat increase is 270ºF per hour.

Color of objects in kiln at this temperature.++ Follow manufacturer’s directions when choosing correct cone number.

These photos are from W.P. Dawson, Inc. Kiln Sitter Operating Manual.If you did not receive a manual with your kiln, we recommend you obtainone from the manufacturer.

During normal use of the kiln, corrosion will occur onthe metal surfaces, which can cause the kiln to misfire. Thetube assembly should be replaced periodically depending onthe amount of firing done. To extend the tube assembly life,keep the lid propped during the early stages of firing and donot close all the peepholes. It is also normal for glaze toaccumulate in the tube assembly; check this periodically.

Kiln sitters, safety timers and computers cannot fullyreplace the operator. Mechanical devices do fail, eventhough they appear to be in perfect working condition. Tominimize errors, always use shelf cone. Avoid leaving thekiln unattended, so you can catch costly mistakes.

Eight Common ProblemsThe cost of the kiln and firing is very high relative to the

cost of the cones. Here are eight good reasons for using shelfcones in addition to using a kiln sitter, kiln timer and/orcomputer.

• Something can fall onto the sensing rod.• Crumbs from exploded ware or from the firebrick can

get into the tube assembly.• Kiln wash on the cone or tube assembly can prevent the

cone from bending.• Using the wrong (or a previously used) cone can be

mistakenly placed into the sitter.• A cone can become dislodged or allowed to come in

contact with the porcelain tube.• Cones mishandled roughly, dropped or moistened will

crack and bend too early.• The weight (hammer) of the sitter may not have

engaged the claw when the cone is placed in it.• Something can get in the way and prevent the weight

(hammer) from falling when the cone bends.

Safety TimerThe safety timer is a back up shut off device that turns

the kiln off if the kiln sitter fails. This clock shuts off thekiln after a given time, insuring that severe damage does notoccur. Set the safety timer for approximately 30 minuteslonger than the estimated firing time; this allows for powerinfluxes and the size of the load. If the timer is set at morethan an hour, it will not turn the kiln off in time to preventdamage from occurring. To ensure the life of your kiln andpieces, safety timers are worth the small initial investmentwhen you purchase your kiln.

ControllersKiln controllers automatically fire a kiln using an

electrical signal from a thermocouple (sensor) located in thekiln. The signal is converted into a temperature and comparedwith a program, allowing the controller to decide when tosend current to the heating elements and for how long. Benefits of using a controller include:

• Automatic, repeatable and accurate control of kiln • Uniform kiln temperatures with zone control • Easy to use with many features

PyrometerA pyrometer is a device that measures temperature

only. It cannot replace a pyrometric cone, because bothtime and temperature are required to ensure the "heatwork"of the kiln. A pyrometer is useful in determining the insidetemperature of the kiln for advancement of switches orgauging the cooling process.

Kiln FurnitureKiln furniture consists of the posts, shelves and supports

(stilts) that are used during firing. These pieces are hightemperature resistant refractory materials that provide supportto the pieces during the firing. Use three posts in a tripodformation to evenly hold a shelf. Each half shelf should rest onthree posts as well. Posts of proportional size should be usedfor added height to ensure stability. Do not use cracked shelvesor posts as they could break apart during the firing, ruiningseveral layers of ware and the kiln. If a crack should developin a shelf because of a hard blow, finish breaking it and use itas a partial shelf.

Kiln WashKiln wash is a protective coating applied to the top

surface of the shelves. This coating provides a layer ofprotection against glaze and other higher firing clays fromadhering to the kiln shelf.

9

Firing

Push Plunger in toactivate kiln.

View AView B

SensingRod

ConeSupports

Porcelain Tube

Proper Formation of Cones in Well-Adjusted Kiln Sitter

Underfired OverfiredCorrect AdjustmentApproximately 90˚

angle

View C

Apply three thin coats (milk consistency) to the top ofeach kiln shelf with a large house brush. Allow to drycompletely before firing. Kiln wash is not applied to the lid,sitter, elements, or the undersides of the shelves. Kiln washwill last many firings and it is not necessary to reapplyunless the surface has flaked or has a lot of glaze build up onthem. Simply scrape off any buildups of glaze with a puttyknife. If glaze remains on the shelf, use a belt sander withcoarse grit to remove it and then reapply kiln wash. A newapplication of kiln wash is required prior to firing any glassin the kiln.

PeepholesPeepholes are exactly what the name infers: openings in

the kiln wall that allow you to view inside the firingchamber. They allow air circulation into the kiln chamberand permit fumes and gases to escape during firing.

Peepholes can have either plugs or hinged coverings.The top peephole should never be closed in a standard bisque,glaze or luster firing until the kiln has shut off. The lowerpeepholes should always remain closed throughout the firing,as they can cause two things to happen. An open peepholecan chill the shelf cone causing it to perform inaccurately.Leaving the peepholes open during any kind of firing cancause a piece to fracture due to a draft onto the ware. Whenfiring glass, all peepholes should be closed during the entirefiring to prevent cold drafts from fracturing the glass.

StiltsStilts are bisque platforms with nichrome wire points that

keep the glaze pieces from adhering to the shelf. They come invarious sizes and heights, allowing the best heat and air circu-lation to the ware during firing. Most stilts are composed of athree prong configuration to give the best degree of stability tothe ware. There are also multi-pronged stilts for accommo-dating larger items. Use the largest stilt to fit the size of thepiece to ensure support. Taller stilts should be used for brightbisque red and orange glazes for better air circulation.

Maintain your stilts by cleaning the points regularly with apair of pliers; if the stilt has a glaze-like surface, it needs to bereplaced. Use of old stilts can discolor the glaze on the piece.

Firing's Four BasicsUnderstanding the basic equipment now leads us to what

happens during the firing process. There are four veryimportant factors required to complete a properly fired piece:Time, Temperature, Air Circulation and Ventilation.Other factors that happen during the firing are: air expansion,ware shrinkage, and how all these factors interact.

• Time is the length that the piece is subjected to heat.• Temperature is the degree of heat required to mature

the piece. Time and temperature combined are referredto as "heat work." This is a very important term toknow and understand.

• Air Circulation is the way movement of air occurs inthe firing chamber.

• Ventilation is the removal of the fumes and gasesduring the firing. Air circulation and ventilation are

independent and are often confused.

Venting SystemsNew kilns come equipped with mechanical ventilation

systems; older kilns can be retrofitted with them. Systemsthat pull the air through a hole(s) in the top of the kilnmaintain a more even temperature throughout the firingchamber. The oxygen that is pulled through the opening(s)allows the glazes to develop better during firing. Never placea piece directly below one of the top vent holes; it can causea cold spot on the piece, making it crack during firing.

Firing Preparation• Maintain your kiln by vacuuming on a regular basis,

and making sure the kiln sitter is adjusted, as they canbecome out of line over time.

• Glazed ware or greenware with trapped air pockets (forexample, hollow arms or handle attachments) should bevented.

• Greenware and glazes should be bone dry. Unnecessarymoisture can affect the glaze or ware, creating bubbles,craters, glaze crawling, or explosion of the piece.

• Pieces glazed inside and out take longer drying time.• Turn kiln to OFF.

Loading the KilnKeep the four basics of firing

(time, temperature, air circulationand ventilation) in mindwhen loading the kiln.When arranging the ware,consider the heat penetration.Air and heat cannot circulateon the kiln floor. Therefore,the first thing to do is createa "false bottom" on the kilnfloor. Place three 1

⁄2” postsunder a kiln shelf; this shelfwill remain in the chamber atall times. The improved aircirculation and heat distri-bution helps overcome stressin the pieces and other problems in subsequent firings, likecrazing, pinholes, cloudy glazes and ware warping.

Heating every piece evenly requires you to load avariety of pieces on each shelf when possible. Never put allof the same shape on the same shelf.

• A good rule to follow when placing pieces in the kiln is aminimum of two finger spacing for greenware and threefinger spacing for glazes (approximately 2 1

⁄2".) Increasespacing to four fingers (approximately 3 1

⁄2") for glassfirings. If you are firing a smaller load, increase thespacing and spread the ware evenly around the kiln.

• Lids should be placed on the piece during a greenwarefiring. Never put pieces inside larger pieces during firing.

• You may prevent warping by "boxing" cups and placingthem rim to rim on top of one another during agreenware firing.

10

Firing

If a glazed piece feelscold to the touch, itindicates that thepiece is still damp

and needs additionaldrying time before

firing.

• Do not place the rims of large plates and bowls nextto an element: this will heat the piece unevenly.

• Flat pieces should be placed on shelves above thebottom two rows of elements for even firing. In thisinstance, it's better to use two half shelves, leaving asmall 3/8” to 1/2” gap between them to promote betterheat and air circulation.

• Generally larger pieces go toward the top of the kiln. • Large volume pieces should be centered in the

chamber with smaller pieces surrounding the ware. • Flat objects are never set on end and should be set flat

on a shelf with no overhanging parts.

While electric kilns are designed for optimum heatingthroughout, a heavily filled kiln will not fire accurately.For a bisque firing, allow at least one inch between thetallest piece and the shelf above it. During glaze firing, atwo inch or more clearance is best before the shelf is putin place. At times when you have only a few items to fire,compensate by "false loading" the kiln with a few extrashelves and/or posts to act like other pieces in the kiln.

If you suspect that you are firing too fast and the wareis not receiving the proper heat work, check your firing byplacing a shelf cone in the center of the kiln shelf andcover it with an unglazed greenware or bisque bowl or pot.After the firing, examine the cone to see if it has deformedproperly. If it did not, you are firing too fast and need toslow the rate of firing.

Kiln firing has some basics. If you have switches thatread Off, Low, Medium and High or have numbering from0-100, the following schedule will help you. The switchesare not turned up concurrently; this would cause anoverfiring in the top and an underfiring in the bottom ofthe kiln. The switches are stepped up in stages tocompensate for the heat rising. An hour between turningup switches is a common time frame.

While every loaded kiln and cone temperature isdifferent, you can modify the firing schedule. A heavierload or heavier types of ware may take longer in the earlyadvancement of the switches. This timetable can bemodified to fit any kiln by any kiln manufacturer. Themanual for your kiln should give you guidelines for firingrates and advancement of the switches and/or dials. Afteryour first few firings, the personality of your kiln willdictate your schedule. Remember that over time the kiln'spersonality can change; using shelf cones will help youmonitor this. The time table below may sound like and

extravagant scheme for firing, but it will give reliableresults, whether it is a low fire glaze, high fire glaze orgreenware.

If you have a computer programmable kiln, follow thesimple directions as it queues you. Generally the direc-tions are on the side of the kiln. Remember that a 250˚ to350˚ acceleration rate is best. Do not allow yourself to betricked into thinking that the computer automaticallyperforms correctly, always use shelf cones to verify theheat work of the kiln.

Kiln SoakingThere are times when you need to "soak" the kiln load.

This is where the kiln, after it has shut off, is restarted andthe switches are turned back to medium for 30-45 minutes.This can be achieved by pushing the plunger back in on thekiln sitter. After the duration of this time, it is shut off againby pushing down the hammer to turn off the kiln. If you donot have a timer, this must be watched carefully. This can bedone with a manual or computerized kiln. Check your kilnmanual for more information.

Changes that Happen During FiringIt is important to understand what happens to the ware

in each firing. During the early stages of firing (at approxi-mately 100˚-300˚), physical water is driven out of the clayand glazes. Rapid temperature increase could trap watermolecules in the ware or glaze; a long slow advancementperiod during this temperature range is quite beneficial. Atthis stage, the kiln lid should be propped three to six inchesto allow the water vapor to escape.

As the temperature rises through the 500˚ to 1300˚range, impurities in the clay and organic matter are burnedout of the ware. Chemically released water and gases aredriven out of the ware as well. Good ventilation is veryimportant during this time; if there is not adequate venti-lation, glazes may become discolored during this stage.

At around 660˚ to 700˚, greenware transforms frombisque and can no longer change back into a lump of clay.This term is referred to as "soft bisque." The ware can stillbe cleaned and handled, but does not crumble as before.

At approximately 1000˚, quartz inversion takes place,turning the quartz in the clay into a crystalline structure.During this time, pieces actually move in the kiln. As witheverything that is subjected to heat, the ware expands, subse-quently shrinking as it cools. When you compare agreenware piece to a bisque piece, the difference is the“shrinkage rate" of the clay. With most whiteware, theshrinkage rate is 4%-10%. Poorly balanced pieces cantopple during this stage. Using kiln wash on the shelveshelps the pieces glide on the shelves during this expansionand shrinkage. This stage produces the most stress on thepiece and happens every time a piece is fired. Thisconversion of the quartz should take place at a slow rate,both during the acceleration and cooling.

OverfiringAll clays have a maturing point; once the temperature

11

Firing

Switches Settings1 2 3 4 5 6

Lid Propped Lid ClosedTop Off Low Low Med Med HighMiddle Low Low Med Med High HighBottom Med High High High High High

Top Peep Hole Open/ All Others Plugged

exceeds this point, the clay actually starts to soften orbecome liquid-like. Although the overfiring may not benoticeable to the naked eye, some indications are that thebisque is hard to glaze, underglazes appear darker or fainter,or glaze colors seem washed out. The ware will also seemdenser or smaller than normal, due to shrinkage.

UnderfiringThe complete opposite of overfiring is underfiring.

Underfiring may not be evident until the ware has been glazedand used. Greenware or bisque can sound hollow or brittle. Aglaze that performs poorly maybe caused from underfiredgreenware or even underfired glaze. Problems that can occurare: blistering, crazing, pinholes, gray discolorations andblack specks in the ware or glaze surface. Fractured pieces canbe directly associated with underfired bisque.

Bisque FiringFiring low-fire whiteware greenware to mature the clay is

called a bisque firing. Mayco glazes should be applied tobisque that is fired to a minimum of one cone hotter than theglaze, but a good rule to follow is to fire two cone numbershotter to assure that the minimum of one cone hotter isreached. During the bisque firing, the organic material in thegreenware or clay is burned off as gas. If the bisque firing isnot at least two cones hotter than the following glaze fire,additional gases may be produced and show up as glazedefects such as pinholes, blistering and/or craters. Utilitarianitems should be fired to a minimum of two cones hotter tomake the ware denser and more durable. Check with yourclay manufacturer to make sure it can withstand these temper-atures; some clays start to deform at Cone 03 or 02.

Greenware can be safely set on the shelf if no color hasbeen applied. Generally greenware is not stilted during bisquefiring; if placed on stilts it may soften and deform at the highertemperatures. Greenware prefers to be fired as it naturally sits.Cups and pieces with handles or protruding extensions maydistort during a higher bisque firing (cone 02 or higher).Pieces that are thin at the top and heavy at the bottom, (i.e. aheavy footed bowl) may fire better inverted upside down.Porcelain and stoneware are never stilted in any firing.

Opaque and translucent underglazes are applied togreenware and mature at the same temperature as thebisque. Underglazes are clay with color pigments addedthat are formulated to shrink and develop during the bisquefiring temperatures. If an underglaze seems not dark or richenough, it may be underfired. Underglazes that seem darkmay be overfired. Applying underglazes on bisque can leadto disappointing results, such as faded color or as a defectcalled "shivering," where the underglaze has not shrunk atthe same ratio as the ware.

Glaze FiringAll glazes all have a maturation point to which they should

be fired. This is stated on each jar on the label. The importantthing to remember is that a glaze firing is a minimum of onecone lower (cooler) than the bisque firing temperature.However, a two cone difference is recommended to avoid glaze

defects, as discussed above. Glazes that are labeled dinnerwaresafe are only dinnerware safe when the shelf cone stated in theinstructions has been reached. Glazes that are underfired mayappear cloudy or milky and lack the proper sheen to the surface.Sometimes glazes can be manipulated to accomplish a specificeffect by firing to different temperatures.

All glazed objects need to be stilted when possible,excluding stoneware and porcelain. Stilts should be fitted to thesize of the object being stilted. Undersized stilts can cause theware to shift in the kiln and could cause the piece to deform.Dry-footing should be discouraged at all times (excludingstoneware and porcelain, where it is required.) Dry-footing isthe removal of the glaze on the bottom surface where the waretouches the kiln shelf. While some pieces cannot be stilted, dry-footing is a last resort procedure.

Glaze is like sugar that is being made into candy. Think ofthe sugar starting out as fine granules. As heat is applied to thesugar it starts to melt, bubbling and boiling, as glaze does on theware. This is why the heat work is so important. The glazeneeds to come to a boil and then smooth out to a hardcrystalline surface, just like candy. If the firing procedure isinterrupted at any point, problems can occur, such as pinholes,bubbles trapped in the glaze or blisters in the surface. If thecooling is too rapid, these problems do not have a chance toheal themselves.

Mayco glazes are referred to as oxidation glazes; theyrequire oxygen to develop fully in the kiln environment. Theabsence of oxygen can change the color greatly, especially forbright reds. Give glazed pieces plenty of room to breatheduring the firing. Giving reds a bit more room than normal aidstheir development. If glazed pieces are put too close to oneanother the oxides in the glaze react with the adjacent color; thisis referred to as fuming, flashing, blushing or shadowing. Itmay also appear as a yellow cast on light colored glazes.

Unlike some competitor’s glazes, all Mayco glazes canbe fired with one another, including green and reds. Mayco'sbisque glazes, bright reds, and oranges due not require aspecial firing when mixed with other glaze colors like greens.However these pieces should be put on higher stilts to allowfor better air circulation. Give them wider berths in their kilnplacement, including the placement of shelves over thosepieces. The use of other companies’ colors used inconjunction with Mayco colors can not be assumed orensured; test fire their compatibility prior to applying colorson a project.

Whether firing whiteware (earthenware), porcelain,stoneware or glazes, make certain you have a thoroughknowledge of what you are placing in your kiln. The properprecautions and actions will ensure a product you will beproud of. Now you are all fired up to operate your own kiln.

Tips for Firing and Surviving in the ClassroomBisque Firing

Dry greenware can touch in a bisque kiln. Bowls and cupsare best stacked rim-to-rim or foot-to-foot. Stack smaller piecesin larger pieces. Don’t stack objects that are a tight fit togetheror have projects touch the elements.

12

Firing

Glaze FiringMany of the low fire glazes work on greenware

(unfired) projects. Most all clear glazes work well, testothers. These pieces need to be absolutely dry after glazingand fired like a bisque firing. The good news is you save

one firing. The bad news isthat if something explodes ina kiln, the exploded glazedpiece sticks to other pieces.This can only be removedwith a grinder or Dremeltool.

Cadmium reds can bevery temperamental. If notapplied or fired incorrectlythey turn a transparent gray.The mauve, rosy colors areless temperamental, but ifyou feel the need for red andit doesn’t work for you try:

• A heavier application of glaze

• Leave more room around pieces or peeps out, as they like oxygen.

• Fire faster

Cracks and Breakage:Greenware is extremely

brittle. Repairing studentwork can be tricky. Mayco,as well as many othermanufacturers, sell productsto repair greenware.

Cracks do not automati-cally happen. It is usually

because the project has a thick and thin piece attachedtogether. The thinner piece dries and shrinks away from theother. If you are making thick animals with 4th graders theymay need to be hollowed out from the underside with a looptool. Poking holes with a needle took or bamboo skewermay also help in drying and firing.

Explosions in kilns are usually from one of two things:• The work is not completely dry. The dryer the better.

If there is a small particle of water on the interior of a clayproject, it has to migrate to the surface to evaporate. If itdoesn’t have a chance to evaporate, it will turn to steamwhen fired and the piece will break in the kiln.

• Air Pockets. If students put two pieces together withair trapped between them, it is necessary to pierce thework with a pin tool to let the air out. This can be a verysmall hole in a place that is not visible. If the air pocket istrapped when the kiln is fired it will expand while the claycontracts and the piece will break when fired in the kiln.

13

Firing

If a teacher does nothave enough kilnspace for separatebisque and glaze

firing, save time bydoing a single firingwhen using Stroke &

Coat®. Many otherMayco products canbe used in a singlefire process. Test

them individually.

If you need tocombine a glaze fire

and bisque fire, placethe glaze pieces in thecooler part of the kilnand the clay pieces in

the hotter part.

Putting Down a Foundation . . .Underglazes

14

Underglazes, originally, was a term used to refer toceramic colors used under-the-glaze, like a foundation. Theterm has now become a general term and a specific materialmeaning. Generally the term refers to a product put ongreenware that is covered with a clear glaze. This can be atranslucent or opaque type of material. The translucent typesare referred to as "One Strokes" and are usually covered witha glaze as well.

The use and application of both opaque and translucentunderglazes are varied. They can be intermixed in eachseparate category or intermixed between the two. Anoversimplification is: Opaque Underglazes are mostly claywith pigment and One Strokes are mostly pigment with littleclay. The amount of clay determines the opacity of theproduct and requires the product to be applied to greenwareso that the products shrink at the same rate in the firing.

Application of Opaque Underglazes• Applied to greenware.• Lightly dampen ware with water before painting; this

allows better adhesion to the ware and helps alleviatepinholes.

• Shake the jar well before applying. It should be theconsistency of melted ice cream.

• Applied with a soft brush. Ox hair or Sable brushes arebest. Can be applied with other methods, see below.

• Use the largest brush for the area covered.• Apply three even smooth coats at right angles to one

another.• Do not thin for general application.• Can be intermixed to get more colors.• Can be tinted with One Strokes.• Fired to shelf cone 04. • Water soluble.• Thin with Mayco Media or water.• All are non-toxic • Generally a clear glaze finish is applied after firing to

bring out the true color and vividness of the product.

Underglazes can be used directly from the jar, butshould be put out onto a tile. Make sure the consistency isthe proper thickness, like melted ice cream. Dip thedampened, blotted brush into the color. Fully load thebrush without dragging the brush on the side of the tile.Apply the color in a flowing motion, if it starts to drag,reload the brush. The clay will absorb the moisture fromthe color, so care has to be used in the application. As youflow the color on, avoid any ridges and runs. Brush theseflaws out as you are applying the color. On an embossedpiece do not allow excess color to build up. Brush theexcess out of the crevices as you apply the underglaze.Apply the first coat; when the dark wet look has left, applythe second coat at a right angle to the first; the third isapplied at a right angle to the second coat. This will assuresmoother coverage.

Sponging Opaque UnderglazesA sponge is used to apply underglaze to greenware when

texturing a surface, when graduating colors, or when blendingtwo or more colors on the same piece. A sponge can be usedon an embossed piece. It works well on large surfaces to geta more even coverage.

A natural sponge works best for applying the color. Makesure the sponge is not worn out or has been exposed to hotwater. It should have a general spring to it. The colorthickness should be the same as for general brushing. Aslightly dampened sponge is used and the color should be putout onto a tile for better application and absorption into thesponge. Pat the color onto the surface in an up and downmotion, with quick motion to avoid smearing or overloadingof the area. Place one dab next to and slightly overlapping ofthe previous one completing the piece in a systematic way.The sponge should be reloaded often. Apply four to fivecoats of color to make up the difference of not using a brush.

Other Application MethodsThere are several ways of applying underglazes other than

the two previous methods. Banding: The color is applied onto a surface using a

banding wheel. The color should be slightly thinner to carry itfrom the brush to the ware. Naturally the piece is round andbands or stripes of color are applied while the wheel is turning.The ware is moistened so the color does not grab from thebrush and the color can be thinned slightly with Mayco Mediato lessen the color from grabbing the ware.

Spattering: The color is spattered onto the ware giving aspeckled look. Using a spatter brush or stiff brush, the color isloaded into the brush, then the handle end of another brush isdrawn towards you over the bristles of the loaded brush. Makesure you protect the work surface because the speckles cantravel great distances to other projects.

Stippling: Thin the color slightly and spread it onto a tile.Load a stiff brush and wipe off the excess color. Test on a pieceof paper each time the brush is loaded. Hold the brush so thatonly the tips of the bristles will touch the surface of the ware.Pounce the brush up and down, gently tapping the color intoplace. This technique is used for smaller and tighter areas whenneeded. This is good for rims of plates or to fill in design areas.

Embossing: The color is thinned slightly to flow out of thedetailing brush so that several coats can be applied. This willgive a dimensional look to the design. Three coats will beneeded to build color depth.

Polishing Underglaze While the application of an Opaque underglaze can be

applied to ware in many ways from brushing to sponging,there is an interesting technique that is very old. One of themost striking looks is by polishing the surface of the color toproduce a soft sheen. This technique is unobtainable by anyother method and is unique to opaque underglazes. While thesurface is somewhat sealed, it is not waterproof. It is only

used on decorative items and is not suitable for food or drink.Design work done in translucent One Strokes can becompleted and then spot glazed to the design, giving acontrast of texture and surface.

Polishing is accomplished by buffing the opaque under-glaze while it is still damp. A smooth surfaced piece worksbetter for polishing underglaze than an embossed piece.Care must be taken to avoid removing the color from sharpangles and rims; it is easy to scratch the ware accidentallywith your fingernails. Apply the color carefully; any ridgesor buildups of color will affect the end result. Using a silksponge to apply the color will help overcome some of theseproblems. Some colors polish better than others. Those thatdry with a frosty look are less than successful.

• Apply three coats of underglaze with a brush in usualmanner to assure all over coverage. Apply the colorsevenly and smoothly. Do not allow prolonged dryingtime between the coats.

• Thin the same color, half and half, with Mayco Mediaand mix well. Prepare a ball of soft facial tissue or softT-shirt material. Apply the mixture to a small area at atime. An area about the size of the palm of your hand isabout right. When the shiny wet look disappears andthe color will not stick to the pad, polish that areabriskly. The pressure should be light and the movementfast. It is the friction that develops the sheen.

• Continue to apply the color mixture to a small area at atime, each one slightly overlapping the previous one,until all of the piece has been polished. Now buff theentire surface again, without wetting, until a high sheenis developed. If the color looks blotchy, this willdisappear as the piece dries.

• If you wish to add a design with underglaze or OneStroke, be careful not to mar the surface. Use a soft clothto hold the piece. Wait until the piece has thoroughlydried before tracing the design so the surface is notmarred by the pressure of the transferring.

Translucent UnderglazeMayco's One Strokes are translucent underglazes that

have a light, airy look and brilliancy of colors. Mayco's OneStrokes look almost the same color in the bottle as on thefinished piece. This allows mixing, shading and blendingwith them to be done with minimal complications. Theycan be compared to the artist's water colors. The "see-through" characteristics of one strokes allow shading of onecolor over another to achieve depth and dimension.

As the name states, One Strokes infers one stroke of thebrush. While this does not bind the artist, it does make theone generous stroke of color the most beautiful aspect of theproduct. When multiple colors are applied, the thinning ofthe color and thinner layers of the product allow the productto be used to its full advantage. The thinning of the OneStrokes and the amount of the application is adjusted to thenumber of times a color is used on a given area. The finaldepth of color should be no more than a generous stroke ofthe brush with unthinned One Strokes.

Concentrated translucent colors are designed for relatively

thin applications that naturally result from ONE brush stroke.Very heavy applications of color can lead to problems of dryareas, cracking or bare spots where the One Strokes may popoff, taking the clear glaze with it. Bleeding of darker colors ofblue and black may occur, but is generally the result of notfiring the color before glazing or too heavy an application of thetop clear glaze.

If the color is applied too thinly, the color will seem todisappear under the top coat of clear glaze after firing. The OneStroke has to be thick enough so the top glaze does not "canni-balize" it and yet feed the glaze to produce the final color.Thinning with water minimizes the danger of heavy application,but over-diluting can cause the loss of color. Darker colors canwithstand more thinning than lighter shades. The use of MaycoMedia helps suspend the color without diluting it.

Use a palette knife to thin the color onto a tile to theconsistency of light cream for most applications, such aslarge areas, creating bold designs, for sponging and drybrushing with a flat shader brush. The product should be theconsistency of very light cream for banding wheel work anddecorating over unfired glazes. For washes of color,spattering or full brush shading over one color with anothercolor, the consistency should be like milk.

General rules for One Stroke application:• Generally applied to greenware Sometimes applied to

bisque, for special techniques like color washes orMajolica (on top of an unfired glaze).

• Dampen the greenware slightly before applying.• Shake bottle well and if necessary thin with Mayco

Media and/or water.• Can be intermixed to get more colors.• Can be used to tint opaque underglazes, glazes and slip.• Fired to shelf cone 04. • Water soluble.• Non-toxic.• Generally a clear glaze finish is applied after firing to

shelf cone 04 to bring out true color and vividness ofthe product.

Brushing Translucent UnderglazesBecause of the translucent quality of One Strokes, the

direction of the brush stroke is apparent. This makes themideal for artistic detail work and designs.

Although One Strokes will not give a solid coverage,generally they can be used satisfactorily on large areas ifapplied in the described manner. Thin the color to thethickness of whole milk, applying with a flat brush sized forthe area. More than one coat of color thinned properly willproduce a more opaque look.

Sponging One StrokesA sponge can be used in a variety of ways with One

Strokes, achieving a totally different look each way. Unlikethe opaque underglazes that block out color beneath, OneStrokes allow every overlap of the sponge to show. A light,airy look is accomplished by choosing a sponge with aspecific pattern to it, rotating the sponge and using lighter

15

Underglazes

mixtures of color, allowing the bisque to show through bySeveral colors can be blended into the sponge at one time.

Usually One Stokes are thinned to the consistency of lightcream for sponging. Darker shades will block out lightercolors underneath, while lighter shades applied over darkerones gives a shadowing to the area.

Color Washes and Antiquing This technique is done on bisque. Dampen the bisque

surface with water so the color applies more evenly. Create a wash mixture the consistency of milk. Use a large

brush to apply to the embossed area where it flows into therecesses and crevices. The color will have a natural tendency tobe darker in the recesses while automatically highlighting theembossed areas. Mixing the one stroke with Mayco Mediamakes the colors brighter and more evenly distributed.

To antique, apply the color and then remove most of thecolor using a damp sponge, leaving little color in the embossedrecesses. The consistency of the color is of light cream. Toothin of color will cause runs and make the color penetrate thebisque, staining it in a seemingly unsightly manner. When thecolor is too thin, it can also cause the color to shiver off with theglaze after firing. Too thick of color will not allow it to get intoall of the embossed areas and can actually repel the top coat ofclear glaze during the firing. It may cause the color and glazeto pop off.

Allow the color to dry before removing it from the raisedareas with a damp sponge. Follow the contour of the design onthe piece. Wiping the wrong direction will cause you toremove too much color, defeating your goal. Rinse thesponge often to keep the highlighted areas crisp and clean. Toomuch pressure on the sponge will also remove excessiveamounts of color.

You can also antique over a fired underglaze. This can bedone to a piece that has several colors applied to the surface, tie

the piece together for an evenlook. The underglazesshould be fired to shelf cone04 before doing thistechnique. Antiquing with aclear glaze is most effective,but is also quite effectivewith a speckled or clear artglaze.

MajolicaMajolica is a term

borrowed from Italy,meaning the decorating ontop of an unfired glaze.Originally the term meantglaze over a white non-

moving glaze. Now Majolica most often refers to the use ofone strokes over a glaze, a procedure that gives morepredictable results. This type of decoration is used when adesirable color or type of glaze is needed that would mute,mare or discolors the one stroke decoration if it were doneunder the clear glaze.

Apply the desired glaze surface evenly with the properamount of coats for the glaze. Thin the one strokes to theconsistency of light cream or lighter. Two thin applicationsare better than one heavier one to produce the desired effect.Thickness of the color is very important for this technique.

Translucent One Strokes and Opaque underglazes areinterchangeable with most techniques. Creating patterns,banding, spattering and stippling can all be done equallywell with either product. Keeping in mind that One strokesare transparent and regular underglazes are opaque. Twotechniques that you cannot interchange products with arepolishing and Majolica.

16

Underglazes

For a velvety finish tothe fired underglazes,eliminate the secondfiring and application

of clear glaze. Or applya unique look. ApplyStroke & Coat® in aMajolica technique

Use geometric shapes tomake these fun animals:

Ceramic glaze is a glass covering that provides aprotective finish for a porous clay object. Over-simplified,it is a combination of raw materials that reacts to heat toproduce a glass coating on ceramic pieces. Colored andtextured glazes have minerals and additives that produceexciting colors and effects. While the unfired glaze maylook dull, drab, uninteresting and a totally different colorthan before it is subjected to the intense heat of the kiln, ittransforms itself like a butterfly. Some glazes may containdyes that are used to better see where they have beenapplied and burn out during the firing. Glazes makeceramics leak-proof, easy to clean, and beautiful. Glazescome in various colors, surface textures and can be usedalone or in combination with others. Glazes provide onestrokes and opaque underglazes with the protective coatingthat brings life to the underlying colors.

Satisfactory glaze finishes result from proper glazingtechniques which are proofed in the kiln. The kiln is thesecond largest factor in determining the final outcome of theglazed pieces. Glaze is not a paint, but is a combination ofchemicals and raw materials. For this reason, mixing two ormore glazes or varying the thickness of application will notalways give dependable results. Mixing a blue and red glazedoes not produce a purple colored glaze. Sometimes themixing of two matte glazes may not produce another matte,but a gloss glaze. Similarly the mixing of two dinnerwaresafe glazes does not make a dinnerware safe glaze.

Glazes are sometimes referred to as being "soft" and"hard." These terms refer to the amount of movementduring the firing and to the final surface of the glaze. Onewould think that all fired glazes would be considered hard,but some may be easily cut with a knife on a dinner plate,while others withstand repeated use. Other types of glazesproduce special effects like snow, raised designs or metalliclooking finishes. Just remember that if you are experi-menting with combinations of glazes that you may becreating surfaces and textures that behave quite differentlythan when you first started.

Applying GlazesBefore discussing the unlimited choices of glazes,

glaze combinations, glazing techniques, and potentialglazing problems and solutions, we should establish theprocedure of applying an all over coverage of glaze. Thereare several methods of applying glaze, but the mostcommon method used is brushing.

Choosing the right brush ensures the job will have abetter finish. The hair of a good glaze brush should feel softto the touch when dry. Don't be mislead by the starch thebrush manufacturer puts in the brush for display. The brushshould have uniform hair texture regardless of the type ofbristles. Stiff bristled brushes or ones with a mixture of stiffand soft hair can detrimentally affect the final glaze surface.When wet, the brush should be resilient enough to return toits original shape after pressure has been applied. Stiff fan

brushes, bamboo and stain brushes should not be used forgeneral glazing of a piece. The brush should be sized for thetask that it is being used for; a small brush used to cover alarge area will give unsatisfactory results. Do not usebrushes previously used with stains. Glaze can bediscolored by remaining traces of stains held in the brush.

Condition of the raw glaze is as important as even appli-cation and the choice of brush. Usually a few shakes of thejar is all that is needed to condition the glaze fully. However,there are times when a jar of glaze is too full; at times glazemay need to be removed from the jar to help mix the glaze.Never thin a glaze prior to vigorously shaking it. If a glazeshould require thinning, use small amounts of distilled wateror Media. For brush application, the product should be theconsistency of ketchup. If the glaze is so thin that it runs outof the brush before applying it to the ware, the addition ofone or more coats may be needed to get the equivalent of onecoat. Wipe the rim and lid of the jar after use to alleviatedried glaze from accumulating in the jar. The glaze shouldbe strained prior to use if this occurs.

The first loading of the brush is the most important stepin glaze application. Dampen the brush and remove theexcess water. This will ensure the glaze brush is completelyclean and will allow the brush to accept the glaze, making iteasier to flow the glaze onto the ware. The brush can bedipped into the glaze, then pressed against the side of the jarlid or tile to spread the hair and cause them to accept theglaze. Jiggle the brush up and down a few times to the ferrulein order to fully load the reservoir. The brush should lookconsiderably larger and fluffier than it did before. Do notempty the brush by wiping the glaze out again on the rim ofthe jar. If it is necessary to prevent a drip, barely touch therim of the jar. It is important to approach the piece with afully loaded brush.

The brush should always be well loaded and saturated sothat the glaze flows onto the bisque with sufficient thickness.Hold the piece and the brush so the color flows down the hairof the brush. Stay up on the end of the brush, especially ondetailed embossed articles, so that you can "squiggle" theglaze into the recessed areas. If too much pressure is appliedto the brush and bends the hairs, you will be removing moreglaze than you are applying. The glaze should ease intoplace. Do not scrub, but flow the color onto the piece.

When the brush is properly loaded, start flowing on threeor four strokes, going in one direction only. Now, your brushis empty. There is still glaze in it, but the reservoir is goingdry. While the brush is nearly empty and the glaze is stilldamp, look at what you have done. If there are any ridges orglaze pile-ups in the embossed areas, use the brush to pickthem up, without taking away too much glaze. Reload thebrush and continue to glaze until the piece is completed.

Each coat of glaze should be allowed to completely drybefore applying each successive coat. Wet ware does notaccept glaze as readily as dry ware. A glaze is dry when itfeels dry, not necessarily when the shiny wet look is gone.

This is Going to Come Out Green?Glazes

17

If it is not dry, the brush may pick up the glaze, rather thanput it down. If the glaze starts to shift or crawl whilepainting, then more drying time is needed. Crawling canalso be caused by over fired bisque or bisque that has beensitting around too long, collecting a greasy film. Do notforce faster drying with hair dryers; this can cause the glazeto perform badly. If a quicker drying time is needed, useindirect heat or a fan to dry the piece.

When possible, each successive coat of glaze should beapplied at a 45˚ angle to the previous coat to help preventstreaking and unevenness. Do not be afraid of applying toomuch glaze. The problems are more varied when glaze isapplied too heavily, but too thin an application is a much morecommon error. Apply the number of coats recommended onthe jar or the technique that you may be following.

It is difficult to establish exactly what is meant by a "coat"of glaze. The personal traits and work habits of an individualvary the application. What does three coats mean in glazeapplication? Usually a glaze requires three flowing coats for theproper thickness in order for the glaze to perform to the desiredfinish. Three coats could translate to four coats for someonewho is termed a light glazer. While some people may onlyrequire two flowing coats to achieve the right deposit of glazeonto the surface of the ware, some people will need more thanthree coats of glaze. If glaze is applied according to the flowingmethod just described, you should have the right amount for acoat. A good rule to follow is to apply one coat and if there isstill bisque showing through the glaze, do not consider it thefirst coat. When the bisque is fully covered in appearance thenthat would be the first coat. The next two coats would fill therequirements of the three coat term. The thickness of a postcard is about the recommended thickness for proper coverageafter 3 applications. You will learn through glazing pieces overtime whether you are a light or heavy glazer and will adjust theapplication of glazes to fit your individual habits.

Clear glazes require two coats only, unless lusters or firedmetallics are used over them. Using more than two coats ofclear glaze on top of underglazes and one strokes can causethe color to float up into the glaze. When two coats of clearglaze have been applied and allowed to dry completely, itshould not be cold to the touch nor should you be able to seethrough the glaze. If you cannot distinguish the colors under-neath, then sufficient coverage has been made.

Occasionally you will run into problems when you areglazing your ware. Hard spots in the bisque are areas thatresist glaze. Do not try to continually apply glaze to this area.Flow one heavy coat on, letting it dry completely beforeattempting to apply more glaze. With successive coats, glazethe area with a fully loaded brush and a light touch. Each coatmust dry thoroughly or the previous coat will be lifted.

Application of glaze with a sponge is sometimesbeneficial, especially when a textured look is desired or whenan extra smooth application is necessary. For best results, usea silk decorating sponge with spring to it. Synthetic or seawool sponges do not work well for all over glazing; theyproduce a texture or a mottled look.

To apply glaze with a sponge, dampen the sponge andremove the excess water with a paper towel. Pour the glaze

onto a tile, then dip the smoothest area of the sponge into theglaze. Pat the glaze into place, overlapping slightly with eachpat. A light touch will apply glaze; a heavy touch will pick upglaze. Pounce the sponge up and down in a straight motion.Do not slide the sponge across the bisque surface as youwould a brush. Keep the sponge full. Before you reload thesponge, look over what you have done to see if a heavydeposit needs to be picked up and redistributed. Four to fivecoats applied with a sponge is needed to achieve the threebrushed coats required for most glazes.

Textured looks are obtained by applying all the coats witha sea wool sponge, allowing the glaze to dry thoroughlybetween each coat. Non-flowing glazes will actually betextured after firing. Flowing glazes will look pebbled, butfeel smooth to the touch.

Semi-transparent glazes tend to appear streaked anduneven on very smooth pieces if all the glaze is applied with abrush. If the glaze is applied entirely with a sponge, a pebbledlook will happen. The best way to achieve a perfect finish forsemi-transparent glazes is to alternate sponging and brushingthe coats to the surface. Apply four coats with this method.

Rolling A GlazeFor hard to reach spots inside containers, pouring or

rolling a glaze in the inside surface is a simple alternative toglazing with a brush. The inside must be free of any debrisand clay dust. Any clay particles left inside the piece cancause crawling problems. Excessive glaze in or on thebottom of the piece can cause it to split, pit or crawl. Theseproblems can be overcome by making sure the excess glazeis removed by inverting the piece as the glaze dries.

How to Roll:• Choose a gloss glaze if possible. Smoother application is

easier and allows better cleaning of the fired surface.• Thin the glaze to the consistency of light cream using

distilled water or Media. Mix enough glaze to completelycover the area. More glaze is absorbed by the bisqueduring this method due to the extra water. The glaze willbe thicker after rolling it into the inside due to absorption ofthe bisque. Save all excess glaze and mark it accordingly.

• Dump the diluted glaze into the piece and rotate the piecewith a continuous motion, covering the entire insidesurface with glaze. Drain out the excess glaze andcontinue to rotate the piece momentarily to avoid glazepile ups in any one place. Keep the piece inverted to dry.This helps avoid the piece splitting during the firing andavoids pitting of the glaze

• When the glaze is firm, turn the piece upright and checkfor possible missed areas. Glaze these areas with a brush.If a colored glaze was used, apply one or two light coatswith a brush to the top areas that may show. Wipe off anyglaze on the outside surface with a damp sponge.

• After the correction has been made, allow the piece to drybefore completing the rest of the glazing. You may noticethe dye from the glaze migrating to the outside of thepiece. There is no need for alarm as it fires away; theglaze is not moving to the outside surface.

18

Glazes

Choosing a Glaze FinishWhen you glaze a piece you are enhancing its utilitarian

and decorative function, not simply covering it. There is moreto consider than color; the form and function of the pieceshould be considered. Choosing the wrong type of glazedetracts from your piece; the right one enhances the form.

The glaze chosen determines the final character of the clayshape, but the reverse is also true. A glaze may look one wayon a highly embossed shape and entirely different on a slick,plain surface. Crystal glazes on a vertical shape smooths outduring the firing. On a plate, the crystals may pit or bubble.

Variation in the heat treatment during the firing of the kilncan also affect the performance of a glaze. A heavily loadedkiln, a soak period, a hotter temperature, and a refire will allcause glazes to flow a little more than usual and could affectthe color stability. This can be a curse or a blessing dependingon the glaze used and the look that is being achieved.

Using More than One GlazeMany times a ceramic shape suggests a finish of colors

placed side by side. Some beginners get the idea that suchcolor placement is limited to underglazes. You are not limitedto glaze finishes being placed side by side due to their gloss ormatte finish. The majority of Mayco's glazes, if appliedcorrectly, do not flow out of control when fired to shelf cone06. Series 2000 Gloss glazes flow, but only within themselves;they level out but do not bleed together. However, extremelyheavy applications of these glazes or prolonged or repeatedfirings can cause excessive flowing.

Butting glazes is a term used to describe the method ofapplying glazes side by side when no color blending is desired.To butt glazes, you must avoid overlapping glazes. A linedrawn with an ordinary pencil on the bisque will determine theprecise placement of the glazes. While the mark will burnaway in the firing, it does nothing to control the glaze. Onlycare facilitates exact application of the glaze. In butting glazes,the brush is used like a push broom at a 45˚ angle to shove asmall ridge of glaze up to, but not over, the pencil line as thefirst coat is applied. This small roll of glaze should give suffi-cient coverage to the perimeter of the area so that special carewith successive coats is not necessary; they can be applied inthe usual manner.

Butting should be all that is needed to control the flow ofthe glazes unless the glaze application is unusually heavy. Onvertical pieces added safety can be added by cutting throughthe glaze while the glaze is still wet. Use a sharpened greasedbased pencil, following the original pencil mark. The glazewill flow to meet the one glaze and the grease in the pencilprovides enough of a resisting barrier to keep the glaze inplace.

Glaze combinations or the use of one glaze over anotherexploits the differences and characteristics of the wide range ofglazes.

When two or more flowing (or soft) glazes are used oneover another, a blending of the two colors results. The glazenext to the bisque will always dominate the piece because ithas a stronger footing or hold on the bisque. Usually, the

glossier the glaze is, the more it moves in the firing. Heavierapplications of these glossier glazes will produce moredramatic intermingling of the colors. Not all glazes used incombination need to be so free moving. A non-moving glazewill retard the movement of a more active glaze. For example,applying three coats of a moving glaze on the bisque, thenapplying two coats of a non-moving glaze on top, the top glazewill break up into little islands of the matte color. Using a tuffyor chore boy sponge to apply leftover amounts of glaze willcreate a look similar to crystal glazes. Base coat with amoving glaze, apply another glaze on top of the first one, thentuffy sponge the third glaze on top of the previous two.Antiquing with glazes can be a lot of fun.

• It hides flaws in the bisque. • The transparency of the glaze adds dimension to the piece. • Great effects are achieved by antiquing with a matte glaze

under a gloss glaze, as well as the reverse.• Use a highly embossed piece to allow the glaze to fill in

the crevices.• One of the glazes used should be non-moving for best

antiquing results.To antique a piece with glazes, apply one flowing coat to

the entire surface and let it dry. Using a damp sponge, wipe offthe highlights on the piece. Apply two coats of the top glazeover the entire piece while concentrating the last coat on thehigher points of the embellishments.

Majolica is accomplished by applying a non-movingglaze to the entire surface, then doing design work on top ofthe unfired glaze with other glazes. This technique makes thedesign look less rigid and the colors are usually lighter.

There are a number of things to consider when choosingcolors for a majolica technique. Consider the transparency ofthe colors. Lighter colors lose their distinctness over darkercolors. Also consider the intensity of the colors being appliedover one another. The thickness of all the colors combinedonto the surface should be taken into the decision. How theglaze moves during firing should be noted. The shape of thepiece can influence the final outcome as well; a flat pieceversus a vertical piece could dramatically affect the outcome.

Food SafetyWith the fun of doing ceramics, comes the responsibility

of making pieces that could be used for holding food or drink"food safe." While you may not plan on a piece being usedfor food or drink, it should be finished in a food safe mannerif the shape is such, that it could someday be used for food ordrink. Knowledge of who or how the piece will be used inthe future is lost once it is out of your sight.

The condition, shape, glaze finish and firing procedureshould all be considered if a piece is food safe. Whether it iscast ware or hand formed, there should be no areas wherefood bacteria can build up and be difficult to clean, like openhollow handles or undercuts inside the bottom of an object.Areas left intentionally unglazed, whether covered with anacrylic stain or some other covering, make it unsanitary andnot food safe. The glaze and bisque firing come back intoplay to make a piece food safe. Improper firing of either thebisque or glaze could result in crazed glaze, which is unsafe

19

Glazes

for food and drink. However, this may not be apparent untilmonths later when the glaze has delayed crazing of thesurface. All glazes should be from reputable manufacturers.They should have the proper seals from the ASTM guidelinesfor food containers. Remember that food safe glazes, whenmixed together or applied one over the other, combine chemi-cally and could produce a finish that is not food safe. Glazesthat do not meet food safe requirements will only releasecontaminates when in contact with acidic foods. Some glazesdo meet the government's tests but are unsuitable fordinnerware due to their texture or glaze surface. Make your piece safe for food and drink by following thesethree rules:

• Choose only dinnerware safe glazes.• Use acceptable bisque pieces that are smooth and in

good condition.• Fire the piece to the recommended temperatures during

the bisque and glaze fire.A glaze is safe for food when it passes the U.S. governmentstest for lead and cadmium release. A glaze that is unsuitablefor inside surfaces because of their texture can be used on theoutside of containers. It is only the surfaces that will come incontact with food that need to receive extra caution.

Opacity of a GlazeThere are times in the decorating process when there will

be a need to know the opacity or translucency of a glaze. Fewcolors are completely transparent, and since they are a form ofglass, few are completely opaque, but there are lots of stages inbetween. There will be times where a glaze containingspeckles or with slight coloration is preferred. Then there arethe times when you have totally changed your mind and wantto cover up completely the underlying colors. Darker colorsapplied heavily are more opaque. Opaque glazes appliedthinner are still more opaque than lighter colors appliedheavily. This can also be an indication on how carefully toapply the glaze when used alone.

• Clear glazes add no color and will tolerate more variationof the thickness of the application.

• White glazes applied over white clay bodies do not showoverlaps of color.

• Dark and opaque glazes seldom show the unevenness ofthe color's application.

The surface also comes into play when applying the glaze.Transparent or semi-transparent colors appear to flow into thecrevices and accentuate the details. On a smooth surface theseglazes should be applied carefully or the unevenness will showup as colored patches. Applying the three coats at right anglesto the previous one will help alleviate this condition.The codes for the opacity of glazes are:

Clear: the glaze adds only a wet, glossy look and bringsout the true colors underlying on the piece.Transparent: the color underneath is slightly tinted withthe overlying glaze changing the appearance only a littlebit.Semi-transparent: the underglazes underneath these areidentifiable, but are changed by the tone of the glaze overthem.

Semi-opaque: light underglaze colors will not showthrough and dark colors will be muted. This can be veryeffective for shadowing on animals, faces, etc.Opaque: most colors will not show through.

OxidationThe glazes used in ceramics are termed oxidation

glazes. This means they need oxygen to develop their colorduring the firing. Oxidation also describes a chemicalreaction to the glaze with the fired metallic lusters put overthem. This change is due to the amount of copper involvedin the coloration of the glaze. Some colors with little copperin them might only slightly affect the fired metallic luster.Sometimes dramatic effects can be made by deliberatelyputting the fired metallic on the glaze.

The Basics of Applying Glazes• Generally applied to shelf cone 04 bisque. Check for

exceptions under individual glaze categories.• Wipe the piece with a damp sponge before starting.• Shake jar well before using. The thickness should be

about like ketchup.• Use either an Oval Mop or Flat Glaze brush to apply

most glazes. • Apply 3 flowing coats unless otherwise noted on jar.

Clear glazes require only 2 coats. Check individualglaze categories for exceptions.

• Use food safe glazes on all containers for food and drink.• Fire to shelf cone 06 unless otherwise noted on jar.• All are water soluble.

20

Glazes

Sponging is as Easy as . . .

Sponge-on-a-Stick

Make perfect circles withthese sponges. Dampensponge with water, press outexcess. Dip sponge lightly incolor. Place on piece andlightly twist.

Pre-Cut Sponges

Create complicated-looking patterns easily! Dampen

sponge, squeeze out excesswater and blot on paper towel.

Brush color onto sponge.Press onto piece.

Problem Cause SolutionGlazes

Oops, Now What Do I Do?Problems, Causes and Solutions

21

Glaze crawls on inside vase. Usually caused by deposits of claydust in bottom of piece.

Check the inside before glazing andremove any dust from inside the vase.Sometimes can be corrected bythinning glaze and reapplying to barespot and re-firing to original shelfcone.

Crackle glaze piece splits after orduring firing.

Same as above in #3 When applying crackle glaze to theoutside of a piece, bring (apply) theglaze over into the inside about 1 inchto help alleviate this problem.

Vase, cup or tall vertical piececracked in kiln.

a. Thermal shock or expansion of twoor more glazes.

b. Incompatible glazes fromdifferent manufacturers.

c. Too heavy of glaze in bottom of thepiece.

a. Try to use the same type of glazeinside and out when glazing. It'sbetter to use gloss glaze insidepieces, even if matte is usedoutside. Do not use matte glazeinside and a gloss outside.Exceptions are Series 2000.

b. Use glazes from the samemanufacturer to assure compati-bility.

c. After rolling glaze on inside ofpiece, invert piece to drain excessglaze.

Clear glaze shows green, brown and/orblack specks after the glaze fire.

a. Dirty or corroded ferrule of the brush.

b. Brushes used for stains and thenglazes.

a. Black and brown specks are fromiron rust; green is from the nickelcoating on the ferrule. Do not allowbrushes to stand in water.

b. Do not use the same brushes formetallic stains and glazing a piece.Metallic particles left in brush cancontaminate the glaze.

Glaze crawls and leaves bare spots. a. Caused by dirt, dust or oil.

b. Color is too old to use.

c. Color has been frozen.

d. Too heavy an application.

a. Make sure piece is clean beforepainting by wiping down with adamp sponge. Keep hands clean.

b. Color preservative has deterioratedwith age. Do not use old product.

c. Sometimes freezing of the productwill destroy the makeup of theglaze. Do not use glaze after it hasbeen frozen.

From time to time there are problems that arise during the completion of a piece. This chapter is designed to helpyou quickly diagnose the problem, learn the cause and if possible, correct the mishap. The problems are listed in groupsof categories. The problem may be listed more than once in slightly different ways to help you get to the solution.

22

Problems & Solutions

Pinholes in glaze. a. Primarily caused by underfiredbisque. Can also be underfired glazeor a combination of the two firings.

b. Improper glaze application.

a. Fire bisque to shelf cone 04 orhotter and at a slower rampingtemperature. Fire glaze to shelfcone 06. Ware needs a two conedifference in bisque and glazefirings.

b. Try "Polishing" the dry glaze withthe heel of your hand beforefiring. Sometimes pieces can besaved by reglazing and refiring.

Colored glaze is streaky. a. Not enough coats applied; coatsbrushed on instead of "flowed" on.

b. Color not stirred. c. Coats not applied at right angles to

each other.

a. Apply the proper coats per labelinstructions using an Oval Mopbrush. Flow the glaze on evenly.

b. Shake and stir the glaze before use. c. Apply the coats at right angles to

one another, allowing adequatedrying time between coats.Sometimes the piece can be savedby warming the piece; reglazingwith a heavy coat and re-firing.

Craters, Fisheyes, Bubbles, or largepinholes appear in fired glaze.

Caused by gases escaping of duringfiring.a. Underfired bisque.

b. Firing glaze while it is wet.

c. Piece not fired hot enough or piecewas fired or cooled too fast.

a. Make sure bisque is fired to shelfcone 04 or hotter. A two conedifference between bisque and glazeis required.

b. Allow glazes to dry 24 hours prior tofiring.

c. Fire glazes to shelf cone 06 orrecommended cone. Glazes need aneven steady ramping of temperatureand cooling as well. Check firingsection. File down craters andreglaze, refire.

Problem Cause Solution

Clear glaze has green or yellow tintin bottom of bowl, plate, pitcher etc.

Clear glaze was applied too thick. Generally brushing clear glaze needsonly 2 coats. If glaze is rolled inside,thin the glaze slightly and then invertthe piece upside down to drain excess.No correction once fired.

Glaze blisters or bare spots appear onembossed pieces.

a. Air pockets in glaze where it meetsthe bisque when applying the glaze.

b. Grease spots from body oils.

a. Use a flat glaze brush when applyingthe glaze to embossed ware.

b. Clean hands before glazing and wipedown piece with a damp spongebefore glazing. Touch up bare spotswith glaze and refire. File downblister; reglaze and refire.

23

Problems & Solutions

Reds fade in the firing, turning whiteto dark gray.

a. Glaze was applied too thinly.

b. Insufficient ventilation in kilnduring firing.

c. Fired too hot or slow.

a. Reds need 4 coats of glaze. If thishas happened to you before, startapplying the extra coat before firing.Allow to dry completely betweencoats.

b. Allow extra room around the piecein the kiln. Vent the kiln until thekiln has been turned or gone to high.

c. Fire quicker than normal to shelfcone 06. Sometimes can be reglazedand re-fired to correct.

White or black spots in red glaze. Contamination from salts or somethingin the brush.

Make sure your hands, the brush andthe piece are clean before glazing. Donot use the same brush for stains andglazes. Reserve brushes specifically forred glazes. This is difficult to correctafter firing.

Clear Matte is milky. Glaze was applied too heavily. Thin the glaze to a milk consistencyand apply 2-3 coats. Sometimes firinghotter will reduce the milkiness, but thematte glaze will be shinier.

Problem Cause Solution

Dipping glaze has purple or greenline down piece.

Dipping glaze too heavy in one spot,where glaze has been overlapped whiledipping.

Dip each side to a 1/4" of each otherand brush the clear glaze together witha fan brush.

Glaze rolls back. a. The glaze was applied too heavily,without sufficient drying timebetween the applications of color.

b. Piece was fired when it was too wet.

c. Glaze not adhered to previouscoat(s).

d. Oil or grease on piece.

a. Allow glaze to dry between coats,applying thinner coats.

b. After glazing allow 24 hours beforefiring.

c. When applying dots make sure colorhas made sufficient contact to piece.

d. Make sure the surface of ware isclean; wipe down with a dampsponge before decorating and makesure hands are clean. Sometimescorrected by sanding downrollback, reapplying color,reglazing and refiring.

Purple Stroke & Coat colors arediscolored or gray looking.

a. Water vapor escaping during thefiring process is trapped in glaze.

b. Use of non-toxic clear glaze ontop of colors.

a. Allow the piece to dry completelybefore firing. Use a slow ramp speedfor the temperature.

b. Some non-toxic clear glazes react withpurple, producing a white hazy look.Sometimes refiring will help clear upthe color. To achieve the best colordevelopment, clear glaze with either aleaded clear glaze or Mayco’s non-toxic, lead-free dipping glaze, SC-209.

24

Problems & Solutions

Problem Cause Solution

Dipping glaze is too thick. Dipping glaze loses water with usethrough evaporation.

Add small quantities of distilled waterto glaze after dipping multiple pieces.Cover glaze when not in use.

Smeared colors after firing. a. Colors not dry prior to dipping orbrushing.

b. Color dragged or disturbed whilebrushing clear glaze.

c. Incompatibility of othermanufacturer's product.

a. Allow colors to dry completely beforedipping or brushing.

b. Remove excess water from brushbefore dipping in glaze. Water createsa barrier between bristles and glaze.Water softens the underlying colors,enabling it to smear as it is brushed.

c. Some manufacturer’s glazes areheavier and as a result, pull the colorsdown into the glaze during the firing.

Pencil marks or lines left in fired color. a. Pencil too sharp and carves intosurface of ware or color.

b. Wax type of pencil used.

c. Pencil or marking instrument wasused on wet greenware or color.

d. Top color did not cover or fill indesign.

a. Never use a freshly sharpenedpencil. Dull the tip on a piece ofpaper by scribbling several times.

b. Some pencils have a waxy basewhich cause the colors resist (i.e.red marking pencil.)

c. Apply design on top of dry color orgreenware. Use a # 2 soft lead pencilfor best results.

d. Make sure when you fill in a design,you go over the design line slightly.

Grit in glaze. Fired or unfired clay dust in glaze. a. Before the bisque firing, removeexcess dust with a dusting brushand a slightly damp sponge. Wipedown ware before decorating with adamp sponge.

b. Strain dipping glaze using 80 meshor finer sieve. Keep glaze tankcovered when not in use.

Fine black specks in flat ware. a. Dirty thermocouples.

b. Soot being trapped glaze.

c. Aluminum filings from dryingracks.

a. Clean and vacuum kiln, wipe downthermocouples periodically.

b. Allow more space between kilnshelves. Vary the size and shapes ofpieces on the shelves.

c. Use non-metal shelving for dryingware. As the shelves are pulled inand out, the metal surfaces grind anddeposit filings on flat surfaces .

Dipping glaze too thin. Dipping glaze over thinned. Dippingglaze not stirred well.

Only add small quantities of distilledwater to thin glaze. Do not addchemicals to thicken; let waterevaporate to thicken the glaze. Mix for10 minutes using a mechanical drillwith glaze mixing blade.

25

Problems & Solutions

FiringProblem Cause Solution

Blisters, craters and pinholes in glaze. a. Bubbles formed and glaze cooledtoo quickly.

b. The glaze was fired on immaturebisque.

a. Allow kiln to cool slowly, soakingthe kiln. (Turning the kiln back onlow for 1 hour after the kiln has shutitself off.) This allows the glazes toheal after the kiln has shut off. Donot leave kiln unattended.

b. Bisque should be fired two coneshotter than the glaze.

Reds develop darker spots in the color. a. Too heavy of application of color.

b. Insufficient amount of oxygen for theglazes to develop during firing.

a. Four coats of color is required forproper application.

b. Keep kiln propped until the kiln goesonto high. Allow extra room aroundall pieces, including the stilting ofthe piece and the shelves above. Donot place all like sized articles onone shelf during the firing.

Plates have dark gray areas in themiddle.

Unburned carbon not removed fromthe ware.

Do not stack pieces inside one anotherduring the firing. Allow for proper venti-lation and air circulation during the firingprocess. If piece has not been glazed,can be corrected by refiring the piece toone cone hotter. Then glaze as normal.

Greens migrate to light colored glazes. Called oxidation (fuming, shadowingor flashing) where the oxides in theglaze migrate during firing.

Allow the pieces extra room whenloading the kiln. Fire greens on topshelf when possible. Some colors aremore susceptible than others, make atest to ensure this does not happen. Donot mix color companies' productswithout a test first.

Reds have turned gray. a. Insufficient amount of glaze on piece. b. Poor ventilation and air circulation

during firing can greatly affect thecolor.

c. Overfiring of piece.

a. Apply 4 heavy coats of color. b. Allow proper ventilation and

placement of pieces in the kiln duringfiring.

c. Fire reds to shelf cone 06. Do notsoak or slow fire the colors if possible.

Gloss glaze is matte. This is underfired glaze. Fire to the shelf cone mandated on glazelabel. Do not fast cool the glaze firing.

Glaze crackles or crazes after firing. a. Immature bisque.

b. Glaze and body fit problem. This iscalled "coefficient of expansion" ofthe glaze to the clay.

a. Make sure the bisque is fired to theappropriate shelf cone for that clay tomature the ware.

b. Make sure glaze can be fired on thattype of clay.

Pieces melted during the firing. Kiln overfired. Check kiln system to make sure every-thing is in working order. Kiln should becleaned before each firing. Go periodicchecks and maintenance of the tubeassembly and shut off hammer. Neverleave kiln unattended while to avoid thisproblem.

Absorption - The ability of a porous object such as plaster orbisque, to absorb water; the amount of moisture that will soakinto an item.

Accenting - Emphasizing a portion of a design with highlights. Abrighter color; outlining or partial outlining.

Added Spare - Cylinder of metal or plastic used to increase thevolume of slip a mold can contain.

Aesthetic Center - A point in a picture that is just off of deadcenter.

Aging - Letting newly mixed slip or clay set for a prescribed time(days or weeks) without disturbing it. Allows the slip and claytime to blend and align the clay particles properly.

Air Brush - A spray gun used for applying glaze or color with theuse of compressed air. Available in several varieties for workranging from overall coverage to fine detail. Use care and propersafety equipment when air brushing.

Airlock - An air bubble which can interfere with the delivery ofcolor through an airbrush or prevent slip from draining from a mold.

Alcohol, Wood - A solvent for cleaning blanks prior to overglazedecoration, or to clean your brushes with dried acrylic in them.

Alumina - One of the essential ingredients in all clay and glazes.Makes clays plastic and gives glazes their stiffness, preventing theglaze from running.

Analogous - Similar or comparable in certain respects; in color,neighboring colors on the color wheel.

Annealing - To hold at a specific temperature to prevent cracking.Glass must be annealed.

Antiquing - Wiping down applied color, leaving a darker tone inthe crevices to accent details; to give an antique look to an object.

Applique - To apply some material decoration to ware: lace,yarn, clay, etc.

Backing - Paper on which decals are mounted.

Balance - The equal ratio of objects and/or color on two halves ofa picture.

Ball Mill - A porcelain jar filled with flint pebbles and rotatedwith either a wet or dry charge of chemicals. It is used to grindand blend clays and glaze ingredients.

Bands - Rubber bands or adjustable straps used to keep thesections of a mold from opening during the pouring process.

Banding Wheel - A turntable, operated by hand or electricity, tofacilitate decoration or hand building.

Bar - Type of pyrometric cone used to measure the heat work in akiln and then allows the kiln sitter to operate.

Binder - Gum Arabic used to make glazes adhere to the ware.

Bisque - Ceramics that have been fired to the maturing point ofthe clay.

Bisque, Soft - Ceramics that have been fired to Cone 018 to giveadded strength or to set a color. Clay is still workable but can notgo back into solution.

Blistering - Bubbles on a ceramic glaze surface.

Blunger - A container with an agitator for mixing slip.

Body - Refers to the basic material used to make up a piece. Theclay. The body can be a mixture of material such as talc, clays,flint, feldspars and others. Bodies ore often described by theircomposition, as a porcelain body, a white ware (talc) casting body,a jiggering body, a shale body.

Bone China - Clay to which bone ash has been added for translu-cency. Fine china tableware.

Bone dry - Greenware that is completely dry, containing no moisture.

Boxing - Firing two cups or bowls on top of each other, rim torim, to prevent warping.

Brush Cleaner - Type of soap used to clean brushes; removescolor and conditions the brush.

Burnish - To polish; term refers to a type of fired gold luster thathas to be burnished to achieve its true color.

Burnishing Brush - A type of brush containing glass fibersbound together in a cylinder; used to burnish Roman Gold luster.

Burnishing Sand - A very fine textured English sand used topolish Roman Gold Luster.

Camel Hair - Term used for a very soft brush, usually made ofsquirrel or pony hair. Name comes from the man who made the brush.

Casting - The art of pouring slip in a plaster mold; also the objectthus formed.

Casting Slip - A liquid clay used for casting a mold.

Center of Gravity - The point that would be reached at the base ofan object if a weighted line could be dropped from the top center.

Ceramics - In broad terms, any type of clay that is fired into apermanent shape in a kiln. Any fired body.

China - A translucent body, usually imported.

China Blanks - Usually refers to commercially made whiteundecorated china used for china painting.

China Painting - Decoration of china using a type of overglazecolors and enamels.

What's in a Word . . .Glossary

26

Clay - Earth that is relatively pure alumina and silica; one of thematerial used in the manufacture of china and pottery.

Clay Carbon - Specially treated paper that will transfer a mark orpattern to a piece of ware.

Clean-up Tool - Tool used to clean (fettle) the seams ongreenware.

Cold Spot - Area in the kiln that is cooler than the rest of the kiln.

Color Wheel - An arrangement of the primary, secondary andtertiary hues and tones.

Combustion - The process of burning.

Complimentary - Those colors that are directly opposite eachother on the color wheel.

Composition - Arrangement of the parts of a design.

Cone - see pyrometric cone.

Cone Plaque - A cube of refractory material used to hold apyrometric cone at 8˚ angle for proper deformation.

Core Mold - This mold has two or more cavities, but all arepoured through the same pour hole.

Crackle Glaze - A glaze that has been specially formulated toproduce a pattern of hairline cracks.

Craters - Bubbles that break and set as the kiln cools. Some timesreferred to as Fish Eyes.

Crawling - Glaze pulls together or beads up, leaving bare spots onthe bisque.

Crazing - Refers to a glaze defect of hairline cracks that appear ina fired glaze. Can also be used to describe the hairline cracksforming in a crackle glaze.

Critical Temperatures - Room temperature to 212˚F; 660˚F to930˚F chemically combined water is driven out of the ware; 1000˚Fquartz inversion takes place; 1060˚F lowest visible red heat; 1650˚Forange to yellow heat in a kiln.

Cross Hatch - Criss-cross scratched marks where two piece ofclay are to be joined. Also refers to the application of glaze at 45˚angles to the previous coat.

Crystals - Specially formulated colored glazes that have been firedand ground up into various sized bits that melt into a glaze,forming bursts of colors.

Decal - A picture or design, usually overglaze color, sandwichedbetween a backing paper and a protective coating; the decal isslipped from the backing to the ware after a water treatment.

Decorate - To apply a design.

Deflocculate - To thin or increase the flowing quality of slipwithout adding water.

Deformation - Bending of a cone or object.

Dehydration - Loss of water through drying, evaporating or firing.

Density - Proportion of plaster to water; weight of any fluid ascompared to the weight of water.

Divitrification - To take away or destroy the glassy qualities of; tomake opaque, hard and crystalline by prolonged heating. Glasssurface that has a wavy rippled quality to it.

Dominant - The most important part.

Double Pour - Casting the outside of a piece in color and theinside in another color of slip.

Drain - To empty, as in draining a mold.

Drape Mold - A plaster over which a rolled out slab of clay isdraped to make free form dishes, bowls, etc.

Draping - To apply lace or other material to a figurine.

Drybrushing - Producing a feathery effect by using a dry brushwith wet color; used also for animal fur. Can be done with OneStrokes or Acrylics in similar techniques.

Dryfooting - Removing glaze from the portion of a piece thatcomes in contact with the kiln shelf during a glaze firing.

Dunting - Breaking of ware in the kiln from trapped air in thepiece or from thermal shock from uneven heating or cooling.

Earthenware - Non-vitreous (porous) body made from low firingclays.

Earth tones - Buff, red, brown.

Egyptian Paste - Soluble sodium salts mixed with clay. Duringdrying a salt deposit is left on the surface of the clay, which makesthe clay self-glazing during firing.

Electrolyte - A substance which can have both a negative andpositive reaction; Substance which causes the deflocculation of slip.

Elements - Wires that carry the electric current that heats the kiln.

Elephant Ear Sponge - Thin, fine grained natural sponge shapedlike an elephant ear.

Embossing - Creating a raised design.

Emery Stone - An abrasive stone used to remove stilt marks fromthe bottom of ware.

Emphasis - Making one portion of a design more important thanthe rest of the design.

Englobe - A prepared slip which is half way between a glaze and aclay; contains clay, feldspar, flint, flux and colorants.

Essence - Solvent used for thinning gold and lusters.

Etch - To produce a design with the use of acid or mechanical means.

Exfoliation - To come off in layers, flakes or scales.

27

Glossary

Extrude - To draw out; force or press out; force through a narrowopening, as clay.

Face - The outside surface of a mold.

Fat Oil - A china painting medium produced by the evaporation ofgum turpentine.

Ferrule - The metal band that holds the bristles of the brush andthe handle together.

Fettle - To trim the spares from cast pieces or the seam lines fromgreenware.

Fettling Tool - A soft knife or hard blade knife to trim and removethe mold spare or seam line.

Filler - Any material that will promote drying and lessen shrinkageof clay, i.e. grog.

Finger Tool - Needle fine sawtooth tool for cleaning the fingers offigurines. A fine steel tool for the same purpose.

Fire Brick - A refractory brick which withstands high tempera-tures; used in building kilns.

Firing - Maturing ceramic products at recommended heats.

Firing Chamber - The interior of the kiln.

Fit - The adjustment of glaze to the clay; the shrinkage rates arethe same for the glaze and clay to be compatible. Improper fitresults in shivering of the glaze(s).

Fitch Hair - Hair used in making stippling brushes. Hair is stifferthan Camel hair.

Fixative - A coating used to seal or fix colors.

Flashing - A reaction of one glaze onto the surface of another;cause by chrome in the glaze fuming during the firing.

Flint - A form of quartz; a refractory material.

Flocs - Thin, flat oval crystals that cling together and form acompact mass, as in clay.

Flow - To move in firing.

Flux - A substance which will lower the melting point of ceramicproducts.

Foot - Base of ware.

Free form - Having no specific geometric form.

Frit - Glass which has been melted, cooled and ground to a finepowder; used in glaze and enamels.

Fuse - Join by melting together.

Fusion Point - Degree of heat at which particles will melt together.

Gang Mold - Several castings can be produced at the same time inone mold; each casting has its own pour hole.

Glassification - Melting into a glass; i.e. Glaze.

Glaze - A glass coating on a ceramic piece.

Glaze Butting - The specific placement of two glazes together sothey do not run together. a.k.a. Controlled Glazing.

Glaze, Dipping - Type of glaze especially designed for a dippingprocess.

Glaze trailing - The placement of a glaze or color through asqueeze bottle.

Gloss Glaze - A shiny glaze with a high reflective surface, unlike amatte or satin glaze.

Gold, Dry - Chemically pure gold.

Gold, Glass - Gold formulated to flux at cone O22 maturing thecolor.

Gold, Liquid Accent - A form of gold held in colloidalsuspension; fires bright but has less carat content of the gold.

Gold, Liquid Bright - A form of gold held in colloidalsuspension; fires bright, high carat content of gold. A brighter andmore reflective surface than Accent Gold

Gold, Paste - Has a higher gold content than liquid Roman; firesdull, must be burnished.

Gold Roman - Fires dull, must be burnished.

Graining - Creating a wood grain with glaze or acrylic stains;opaque or translucent.

Graphite Paper - Similar to carbon paper; used to transfer designsto china.

Greenware - Clay item before it is subjected to bisque firing.

Grid - A series of uniform squares.

Grind - To eliminate grit from powdered color by mixing with flatside of a palette knife.

Grit Cloth - An abrasive cloth for cleaning greenware.

Grit Pad - A foam backed abrasive pad used in sanding orcleaning.

Grog - Finely ground up bisque added to clays to reduce theshrinkage or for thermal shock.

Gum Arabic - A water soluble gum obtained from several acacias;used in adhesives as a binder.

Gum Tragacanth - A tasteless odorless white or reddish gumobtained from several shrubs; used in glazes to keep material insuspension.

Hard Paste - Refers to a type of very hard fine porcelain.

Hard Spot - A spot on the greenware that resists decoration. Canfollow through to the bisque.

28

Glossary

Hard Bisque - Term given to bisque that is fired to its hottesttemperature before it goes liquid.

Harmonious - A color scheme chosen by some numerical sequence.

Haze - A cloudy deposit on gold or luster cause by insufficientventilation during firing.

Horizon Line - Point at which sky and land or water seem tomeet, at sea level.

Horizontal - Parallel to the horizon.

Hot Spot - Any area in the kiln that fires to a hotter cone than therest of the kiln.

Hump - A plaster shape on which a clay slab can be draped tomake a free form bowl or dish.

Hydrometer - A device to measure the density of a liquid.

Immature Bisque - Bisque which has not been fired to the propertemperature to mature the clay and drive all carbons and impuritiesfrom the ware.

Impervious - Cannot be penetrated.

Incise - To cut into the clay or greenware surface making a design.

Incompatibility - Ceramic materials that cannot be used togetherbecause of undesirable chemical reactions.

Insulating Brick - A soft refractory brick which can be easilycarved and is used to line hobby kilns. Both firebrick andinsulating brick are available in different degrees of refractorinessand should be chosen according to the temperature they mustwithstand.

Intaglio - An incised design in which the carving is done inseveral depths.

Jiggering - Forming a pot between a revolving mold which shapesthe outside and a template which shapes the inside.

Kaolin - A clay used for whiteness in some clay bodies; mainingredient in porcelain.

Key - Notches cut on the seams of a mold so that the sections willalways fit in the same manner.

Kidney - See rubber kidney.

Kiln - A heating chamber for maturing clay glazes and otherceramic materials.

Kiln Furniture - See furniture.

Kiln Wash - A refractory coating for kiln shelves to protect themfrom dripping glaze.

Knead - To condition clay.

Lace Tool - A tool with a needle tip to facilitate the arrangement oflace on a figurine.

Lawn - To sift dry color through closely woven material.

Leach - To cause (a liquid) to filter down through some material; toextract a soluble substance from some material (as lead leachedfrom glaze by an acidic liquid - i.e. orange or tomato juice).

Lead Safe - A glaze that has been tested and meets governmentstandards as safe for food and drink containers.

Leatherhard - Cast or handbuilt pieces that are firm enough tohold their shape without warping, but can still be cut into easily;stick-ons can still be attached.

Liner - A long bristle pointed brush used for lines and scrolls.

Lint-free - Any cloth that does not produce lint; silk, old sheeting,etc.

Lock Washer - Washer used to keep nuts from loosening.

Loading - Filling the brush with color; stacking the kiln.

Luster - An overglaze that gives a lustrous iridescent finish toglazed ware.

Luting - Joining leatherhard clay sections together with slip.

Majolica - Glaze on glaze decoration.

Marbleizing - Creating the effect of marble with any colormedium.

Masking - Blocking out sections of a design that are to to bepainted.

Matte - A dull, non-reflective surface; the opposite of glossy.

Maturity - In ceramics, bisque that has been fired to the pointwhere it will no longer expand when absorbing moisture; pointwhere underglaze, glaze and overglaze reveal their true color andstate (gloss, matte, etc.)

Maturing Point - Temperature where the clay or color becomesfully developed.

Medium - Fluid used with colors to facilitate painting.

Mender - A product to repair broken greenware, or attach stick-ons.

Migrate - Tendency of certain glazes to travel to neighboringpieces during firing; caused by the chrome in the coloring; referredto as Flashing, Fuming or Shadowing.

Mildew - A fungus that produces dark spots on damp molds whenthey are stored without sufficient air circulation; can cause moldsto deteriorate rapidly. Also dark spots developing under glaze onchina that was not glaze and or fired properly.

Mishima - Inlaid slip decoration

Modeling Clay - Clay used for hand building or throwing.

Mold - A plaster form used to produce identical objects by pouringliquid slip into the hollow cavity, then draining.

29

Glossary

Mold Cavity - The hollow section of a mold that is a negative ofthe finished casting. That part which is filled with slip to form thecasting.

Mold Rubber - Liquid rubber used to make stamps of simpledesigns or master molds.

Monochromatic - A color scheme composed of various tints,shades and tones of a single color.

Nichrome- A heat resistant wire.

Nipples - Clay bumps left on the bottom of food and drinkcontainers by improper draining of the mold in pouring. Threadedsections of pipe used to connect lamps.

Non-Toxic - That which is not toxic. Can be used with little worryas to any contaminants and hazardous material in them.

Opacifier - A material used to make a translucent color moreopaque. White is an opacifing color.

Opaque - Not transparent; completely covers any other colorunderneath; does not allow light to filter through.

Open - Refers to a color that remains the form of an insolublepowder, workable for a long period of time.

Overglaze - Any decorating material that is applied on top of afired glaze and has the firing range of cone 022 to 014.

Oxidation - Combining with or reacting to oxygen; iron rust orcombining with oxygen; some green glazes may oxidize and turnblack during an 018 firing.

Palette - Glazed tile or glass on which colors are placed formixing and painting from.

Palette Knife - Flexible knife used for grinding color.

Parallel - Two lines that are the same distance form each otherthroughout their length.

Peephole - Openings in the side of the kiln through which you canview a pyrometric cone.

Perpendicular - A line that is at a right angle to another line.

Perspective - The science of paintings and drawing so that objectsrepresented have apparent depth, distance and third-dimension.

Pierced Carving - A type of design formed by cutouts in theware. Usually done on leatherhard greenware.

Pigments - A coloring agent; usually in the form of an insolublepowder, ground with water, oil or acrylic.

Pinholes - A glaze defect caused by underfiring, glazing ongreenware and or condition of greenware.

Plaster - A white powder made of gypsum; quick setting whenadded to water which molds are made.

Plaster Clay - A non-hardening modeling clay.

Plasticity - The pliability of modeling clay.

Plug - A cone shaped section of refractory material used to closethe peepholes in the kiln during firing.

Polish - To buff to a shine.

Pooling, Puddling - Glaze which runs to the bottom of a bowl ordishes or fills in the crevices.

Porcelain - A high-fire translucent, vitreous body.

Porosity - The ability of an object to absorb moisture.

Posts - Square, triangular or cylindrical sections of refractorymaterial used to support shelves in the kiln; may be stacked.

Potters Wheel - Used for throwing clay pots; may be manually orelectrically driven.

Pottery - Any low-fire object formed from clay.

Pounce - To pat; also the powdered graphite used to transferpieced patterns.

Pour Gate - Area of mold that slip is poured into; area that holdsthe excess slip to allow for absorption and ensure a proper casting.

Pouring - See Casting.

Press Mold - Shallow molds used by pressing soft clay in thecavities; may also be used by pouring slip in the cavities.

Primary Colors - The three basic colors are Red, Yellow andBlue.

Prism - Three sided glass or crystal object that breaks up light intorainbow colors.

Pug Mill - A machine for mixing and extruding plastic clay.

Pyrometer - An instrument for measuring degrees of heat beyondthose shown on the average thermometer.

Pyrometric Cone - Pyramids; compounded of ceramic materialscontrolled to melt as specific time, temperature relationships usedto control heat treatment of ceramic products.

Quill - A type of brush used for china painting.

Raw Glaze - A glaze that contains no fritted material.

Raised Paste - An overglaze material used for a base for a raisedgold design.

Red Heat - Point at which the interior walls of the kiln and theware glow red; 1060˚ F.

Reduction Firing - Firing with a reduced oxygen supply.Opposite of Oxygen firing, which is what low-fire glazes need todevelop.

Refractory - Materials that are hard to melt or work.

30

Glossary

Release Time - Length of time needed before a casting can beremoved from a mold.

Relief - A raised design.

Renuzit - A dry cleaning material used to clean rubber stamps.

Rib - A rubber, metal or wooden tool used to facilitate wheelthrowing of ceramic forms.

Rod, Actuating - That portion of the kiln sitter which drops as thecone deforms, causing the kiln to shut off.

Rolling Glaze - Covering the inside of ware by pouring in thinnedglaze, rolling it around the inside surface and then pouring it out.

Rouging - Applying color lightly with cloth or finger, or with a pounce.

Rubber Kidney - A kidney shaped piece of hard rubber used inshaping wheel-thrown pieces.

Running - The fluidity of a glaze at its maturing point and before itcools and hardens.

Rhythm - The flow and movement of lines and color in a design.

Sagger - A refractory support for firing porcelain plates and othershapes that might warp from their own weight; also a support forfiring glass.

Sable - Animal hair used to make the finest, most resilient brushes.Red sable is considered the finest of the hair types.

Satin - A glaze that produces a soft sheen between a gloss and amatte surface.

Saturation Point - Point at which an object can absorb no moremoisture.

Scoring - The marking into the surface of the piece.

Scum - A haze that forms on fired gold and luster from insufficientventilation in the kiln.

Sealer - A coating which closes the pores of bisque or other porousmaterials.

Seam - The ridge left on greenware at points where the moldsections join. The surface areas of a mold that meet when the moldis banded together.

Secondary - Those colors on the color wheel that are made bymixing two primary colors together; green, violet and orange.

Set-Up-Time - Length of time that casting slip must remain in themold to form the wall of the casting.

Setter - A refractory holder on which porcelain dishes are fired toprevent warping; see saggers.

Settle Out - Particles of color settle to the bottom of the jar whenthe water balance is disturbed.

Sgraffito - Cutting through color or a layer of colored clay to producea design.

Shade - Any hue that has been deepened by the addition of black.See tints and tones.

Shelf Cone - Pyrometric cone used to tell the temperature at whichthe temperature on the shelf has been completed using heat work.The actual cone temperature.

Shelf Support - See Post.

Shivering - Where glaze peels off from the ware because the wareshrinks more than the glaze; a body fit problem.

Short - Stiff clay body caused by low moisture content; lackingplasticity.

Shrinkage - Decrease in the size of the clay object as a result ofdrying and firing. About 5 percent in low-fire.

Silica - One of the basic ingredients in glaze.

Silicate of Soda - Water glass. See Sodium Silicate.

Silk Sponge - A fine textured sponge used for decorating.

Sitter - A device that is activated by the deformation of apyrometric cone, causing the kiln to shut off.

Slab - A rolled out section of clay.

Slake - To reclaim dried up clay; it is pounded into small piecesand covered with water; only completely dry clay can be slaked. Allmodeling clay may be reclaimed. However, reclaiming clay toreturn to the slip batch is a dangerous practice and should beavoided.

Sling - Burlap used to cradle clay to make a slab bowl.

Slip - A fluid suspension of clay and other chemical materials inwater.

Slip Trailing - Decorating leatherhard greenware with slip appliedfrom a bulb or bottle with a narrow nozzle.

Slurry - A clay body of creamy consistency; used for joining moistclay together.

Soak - To hold a kiln at one temperature for a period of time.

Soda Ash - A deflocculent.

Sodium Silicate - Water Glass; a deflocculent.

Soft Fire - Greenware fired to cone 018; accepts underglaze colorin the same manner as greenware but is more durable.

Soluble - Able to be dissolved in water.

Solvent - Any fluid that will dissolve or remove color.

Spare - The scrap of clay that is cut off of every casting an area ofthe mold that increases the volume of the mold; see pour gate.

Sponge - See specific types of sponges; seawool, silk or elephant.

Spatter - Method of applying flecks of color, usually with a bristle brush

31

Glossary

Spray - To apply color by means of some type of air supply.

Sprig - A clay trim, made in a press mold and attached to aleatherhard casting with mending slip.

Spur - A metal tripod used to stilt glazes ware during the firing.

Stack - To load the kiln.

Stain - Acrylic type of non-fired paint used to decorate bisque; aclay or glaze pigment.

Stamp - A raised rubber pattern used to transfer or apply a design;a fired clay cylinder used to texture clay slaps or pots.

Stamping Oil - Medium used with rubber stamps to hold dry colorto design.

Stencil - A cut-out pattern used to apply a design by brushing,sponging, stippling or spraying.

Stick-On - Handles, knobs, sprigs or any attachment to a casting.

Stilt - A refractory tripod or bar with nichrome wire prongs used toraise ware off the kiln shelf during a glaze or overglaze firing.

Stipple - To apply color with a series of tiny dots.

Stippler - A brush used to produce a series of tiny dots; also usedto blend colors.

Stoneware - A clay to which a high percentage of grog has beenadded; Needs to be high-fired to vitrify.

Strength - The percentage of pure color in a shade, tint or wash.

Stylus - A pointed instrument for writing or drawing. Used totransfer a design.

Subdominant - Less important part of a design.

Talc - Used as a flux for clay; also used as a mold release.

Tint - Hue made with the addition of white.

Tipping - Involves touching tip of loaded brush with other colorsfor muted shading or accenting

Thermal Shock - The abrupt change of temperature to the ware.

Template - A pattern or guide.

Tone - Color plus a neutral gray.

Toxic - Poisonous.

Translucent - Able to transmit light as frosted glass, parchment,sheer fabric. Diffuses the color or light.

Transparent - Easily seen through as glass. No interruption oflight or color.

Underglaze - A mineral color, usually containing some clay andbinder; regular underglazes are opaque and contain a higher

percentage of clay than One Strokes; most One Strokes aretranslucent.

Utilitarian Ware - Any object that will hold or contain food orliquid drink.

Vanishing Point - A point on the horizon line at which the lines ofan object appear to converge; see perspective.

Venting - Propping the lid of the kiln open to slight degree orleaving out peephole plugs until moisture and carbonaceousimpurities have been burned out of the greenware. ( Usually untiltemperature reaches red heat). Also the piercing of any portion of acasting in which air could be trapped. ( Trapped air expands withheat and can cause the piece to explode or swell).

Viscosity - The thickness of a liquid; internal friction of a fluid,cause by molecular attraction; resistance to flow.

Vitrified - A body which fuses sufficiently during firing so that itis water tight without glazing.

Vitreous - Water tight.

Warping - Deformation of a clay shape cause by uneven stressesduring shaping, drying or firing.

Wash - A color diluted with water or suitable solvent used forshading and antiquing.

Water Glass - Silicate of soda; mender and deflocculent.

Water Smoking - The firing period during which all water isdriven from the ware. Room temperature to 212˚F.

Webbing - Material used for making straps.

Wedge - To condition and work clay into a bubble free mass forthrowing or handbuilding.

Wheel - Turn table operated by foot or electricity for producinground pots.

Witness Cone - See shelf cone.

Wool Sponge, Sea - A very open texture and very absorbentnatural sponge. Used for uneven textures and veiling techniques.

32

Glossary

33

Pro

duct

Sur

face

Fir

ed C

olor

Fir

ing

Ran

geU

ses

Typ

es o

f C

lay

Not

es

Ear

then

war

eP

otte

ry o

rC

eram

ic C

lay

Sto

new

are

Not

Vitr

eous

Not

Tot

ally

Vitr

eous

Usu

ally

whi

te-t

o-of

f-w

hite

Buf

f or

Gra

y in

Col

orSh

elf

cone

06

–10

Opa

que

afte

r fi

ring

Orn

amen

tal a

ndD

inne

rwar

epi

eces

Shel

f co

ne 0

6-02

Opa

que

afte

r fi

ring

Orn

amen

tal a

ndD

inne

rwar

epi

eces

Pug

Cla

y, W

et a

ndD

ry S

lip

Pug

Cla

y, W

et a

ndD

ry S

lip

• Lea

st e

xpen

sive

of a

ll cl

ays.

• Mos

t com

mon

and

eas

iest

to u

se.

• Bis

que

mus

t be

glaz

ed to

mak

e w

ater

tight

; ea

rthen

war

e is

a lo

w-f

ired

poro

us b

ody.

• D

inne

rwar

e ha

s a

grea

ter t

ende

ncy

to c

hip

and

craz

e th

an v

itreo

us w

are.

• Can

be

used

with

bot

h fir

ed a

nd n

on-f

ired

finis

hes.

• C

an b

e us

ed in

a s

lip fo

rm fo

r cas

ting

mol

ds,

for h

and-

built

item

s an

d fo

r whe

el th

row

ing.

• Shr

inks

ver

y lit

tle d

urin

g fir

ing.

• Fire

d in

5 to

7 h

ours

• M

ost h

obby

ist c

an n

ot fi

re s

tone

war

e to

a to

tally

vi

treou

s st

ate

so fo

od a

nd d

rink

cont

aine

rs m

ust b

e gl

azed

.•

Ston

ewar

e is

muc

h st

rong

er a

nd m

ore

chip

resi

stan

t th

an e

arth

enw

are.

• Sh

rinks

in th

e fir

ing

by a

t lea

st 1

5-20

%.

• C

an u

se a

lead

ed g

laze

on

surf

ace

as h

igh

degr

ee o

f he

at a

ttain

ed c

ombi

nes

the

lead

in a

form

that

is n

ot

rele

ased

or l

each

ed o

ut b

y fo

od o

r drin

k.•

Can

be

used

in a

slip

form

for c

astin

g m

olds

, for

han

d-bu

ilt it

ems

and

for w

heel

thro

win

g.•

Can

als

o ad

d gr

og to

stre

ngth

en c

lay

for l

arge

r pie

ces.

• N

eeds

to b

e fir

ed s

low

ly, i

n no

less

than

10

hour

s.

Por

cela

inV

itreo

usN

orm

ally

whi

te; c

anco

me

in s

ome

colo

rsSh

elf

cone

2-1

0.So

me

indu

stri

alpo

rcel

ains

may

rea

chco

ne 3

0. T

rans

luce

ntaf

ter

firi

ng

Din

nerw

are

and

Fine

Det

ail

Item

s

Pug

Cla

y, W

et a

ndD

ry S

lip•

Doe

s no

t nee

d to

be

glaz

ed, p

iece

s th

at a

re to

be

used

for

foo

d or

dri

nk a

re g

laze

d fo

r sa

nita

ry r

easo

ns.

• W

hen

clea

r gl

azed

, por

cela

in b

ecom

es c

hina

.•

Will

shr

ink

in th

e fi

ring

up

to 2

0%.

• N

eeds

to b

e fi

red

slow

ly in

no

less

than

10

hour

s.

CL

AY

Qui

ck R

efer

ence

Gui

de

Pro

duct

Tim

eC

one

Tem

p. &

V

ente

d N

on-v

ente

dN

otes

Ram

ping

Rat

eK

ilnK

iln

34

One

Str

okes

Opa

que

Und

ergl

azes

Ast

ro G

ems

Gla

zes

6-8

hrs.

for

shel

f co

ne 0

4 8-

10 h

rs. f

orsh

elf

cone

6 o

rhi

gher

5.5-

8 hr

s.

Shel

f con

e 04

- 6.

Che

ck H

ighe

rth

an 6

test

ing

for

colo

r hol

d sh

ould

be d

one.

06 –

6

1940

with

350

Ram

ping

Spe

ed;

Mid

-ran

ge c

one

6 -

2194

to 2

232

Hig

h-fir

e to

con

e 9-

10.

1830

with

350

Ram

ping

spe

ed

Clo

se a

nd F

ire

Clo

se a

nd F

ire

Top

peep

hole

left

open

thro

ugho

utfi

ring

.

Top

peep

hole

left

open

thro

ugho

utfi

ring

.

• Pie

ces

shou

ld n

ot to

uch

whe

n lo

adin

g th

e ki

ln.

• Ast

ro G

ems:

rem

ove

larg

e cr

ysta

ls fr

om b

otto

m o

f war

e an

d lid

s. • D

o no

t stil

t gre

enw

are

unle

ss h

ave

too.

Nev

er st

ilt w

hen

high

firin

g.• I

f opa

que

unde

rgla

zes

and

one

stro

kes

are

not a

s da

rk a

s th

e ch

ip c

hart,

they

may

be

unde

rfire

d.

• Pie

ces

can

not t

ouch

whe

n lo

adin

g ki

ln.

• Pie

ces

shou

ld b

e fin

ishe

d on

bot

tom

unl

ess

doin

g st

onew

are

or p

orce

lain

.• S

houl

d st

ilt p

iece

s be

fore

firin

g un

less

firin

g to

con

e 6

or h

ighe

r.• I

f pie

ce is

und

erfir

ed, g

laze

may

app

ear m

ilky

or c

loud

y.

Can

refir

e.• I

f hig

h fir

ed g

laze

s sh

ould

be

appl

ied

to g

reen

war

e or

pie

ces

fired

to 0

4 th

en fi

re to

bis

que.

Lus

ters

31/2

-4 h

rs.

022

018

015

1112

13

2314

7935

0 R

ampi

ng S

peed

Clo

se a

nd F

ire

Top

peep

hole

left

open

and

lid

prop

ped

thro

ugho

utfi

ring

.

• R

ead

prod

uct l

abel

s as

to f

irin

g in

stru

ctio

ns a

nd te

mpe

ratu

re.

• To

o ho

t a f

irin

g ca

n ca

use

defe

cts.

• To

o lo

w o

f a

tem

pera

ture

can

res

ult i

n co

lor

wip

ing

off

afte

r fi

ring

.•

Stilt

all

piec

es.

• Pr

oduc

ts n

eed

extr

a ve

ntin

g ro

om w

hen

load

ing

kiln

.

FIR

ING

Gre

enw

are/

Ear

then

war

e5-

8 hr

s.04

1940

350

Ram

ping

Spe

edC

lose

and

Fir

eTo

p pe

epho

le o

pen

for

firs

t hou

r of

firi

ng.

• Sho

uld

not l

oad

war

e w

hen

wet

and

moi

st.

• Sho

uld

neve

r tou

ch a

noth

er p

iece

dur

ing

firin

g.• R

emov

e al

l exc

ess

dust

prio

r to

firin

g.• D

o no

t stil

t unl

ess

nece

ssar

y.

Qui

ck R

efer

ence

Gui

de

Sto

new

are

Por

cela

in

8-10

hrs

.

8-10

hrs

.

6-10

6-10

2232

– s

helf

con

e 6

350

Ram

ping

Spe

ed

2232

35

0 R

ampi

ng S

peed

Clo

se a

nd F

ire

Clo

se a

nd F

ire

Top

peep

hole

ope

nfo

r fi

rst h

our

offi

ring

.

Clo

se a

nd F

ire

Top

peep

hole

ope

nfo

r fi

rst h

our

offi

ring

.

• Sho

uld

not l

oad

war

e w

hen

wet

and

moi

st.

• Sho

uld

neve

r tou

ch a

noth

er p

iece

dur

ing

firin

g.• R

emov

e al

l exc

ess

dust

prio

r to

firin

g.• D

O N

OT

STIL

T.• M

ust u

se s

epar

ator

on

box

lids

and

piec

es th

at w

ill to

uch.

U

se p

orce

lain

san

d or

alu

min

a hy

dra

as s

epar

ator

.• B

ette

r to

slow

the

firin

g do

wn

than

to fi

re fa

st.

• Sho

uld

not l

oad

war

e w

hen

wet

and

moi

st.

• Sho

uld

neve

r tou

ch a

noth

er p

iece

dur

ing

firin

g.• R

emov

e al

l exc

ess

dust

prio

r to

firin

g.• D

O N

OT

STIL

T.• M

ust u

se s

epar

ator

on

box

lids

and

piec

es th

at w

ill to

uch.

U

se p

orce

lain

san

d or

alu

min

a hy

dra

as s

epar

ator

.• B

ette

r to

slow

the

firin

g do

wn

than

to fi

re fa

st.

Clo

se a

nd F

ire

35

Qui

ck R

efer

ence

Gui

de

Pro

duct

Hea

lth

Sta

tus

May

co B

ook

Fir

ing

Ran

geA

pplie

d B

y:G

ener

al

Not

esA

pplic

atio

n

Opa

que

Und

ergl

azes

N

on-t

oxic

N

on-m

ovin

gw

hen

fire

d.

Pg. 1

9Sh

elf

cone

04-

6.So

me

colo

rs c

anho

ld to

she

lfco

ne 9

-10.

Che

ckH

igh

Fire

Gui

defo

r co

lor

chan

ges

at s

helf

con

e 6.

Bru

sh/S

pong

eG

reen

war

e on

ly.

Can

be

used

toan

tique

det

aile

dbi

sque

.

• R

eady

to u

se fr

om ja

r.• A

pply

in th

ree

even

coa

ts, i

f col

or s

treak

y no

t eno

ugh

colo

r app

lied.

• G

ener

ally

use

d as

an

all o

ver c

over

age.

• C

an b

e po

lishe

d, d

oes

not h

ave

to b

e gl

azed

.•

Inte

rmix

able

• App

ly c

lear

gla

ze a

fter 0

4 fir

ing

to b

ring

out t

rue

colo

r of p

rodu

ct.

Fire

to s

helf

cone

06.

• U

G-8

4, 8

5 &

86

will

all

fire

to s

helf

cone

10.

• If

sur

face

not

gla

zed,

use

Rep

elle

nt S

eale

r AC

-301

to m

ake

soil

resi

stan

t

One

Str

oke™

Tra

nslu

cent

Und

ergl

aze

Non

-tox

ic

Non

-mov

ing

whe

n fi

red.

Pg. 2

2Sh

elf

cone

04-

6.So

me

colo

rs c

anho

ld to

she

lfco

ne 9

-10.

Che

ckH

igh

Fire

Gui

defo

r co

lor

chan

ges

at s

helf

con

e 6.

Bru

sh/S

pong

e

Bru

sh/S

pong

e

Can

be

used

on

gree

nwar

e an

d/or

bisq

ue.

Can

be

used

for d

esig

nw

ork

on to

p of

non-

mov

ing

glaz

efo

r Maj

olic

ate

chni

que

• M

ust t

hin

befo

re u

se; h

ighl

y co

ncen

trate

d co

lor.

Use

AC

-304

Med

iaor

wat

er to

con

ditio

n or

thin

.•

Inte

rmix

able

• Tra

nslu

cent

• U

sed

for b

rush

stro

ke d

esig

ns, i

n on

e st

roke

of t

he b

rush

; can

be

used

in a

ll ov

er c

over

age

with

mul

tiple

coa

ts.

• C

an a

dd to

Opa

que

Und

ergl

azes

, Ast

ro G

ems,

gla

zes

and

liqui

d sl

ip

to ti

nt c

olor

.•

OS

44, 4

5 an

d 46

will

fire

to s

helf

cone

10.

PR

OD

UC

TS

FO

RG

RE

EN

WA

RE

Ast

ro G

em®

Tex

tura

l Gla

zeN

on-t

oxic

N

on-m

ovin

gw

hen

fire

d.

Pg. 2

4Sh

elf

cone

04-

6.C

heck

Hig

h Fi

reG

uide

for

col

orch

ange

s at

she

lfco

ne 6

.

App

ly to

gree

nwar

e or

bis

que.

Gre

enw

are

pref

erre

d du

e to

dryi

ng ti

me

and

fit.

• App

ly in

thre

e ev

en c

oats

.•

Inte

rmix

able

• Sur

face

is s

tone

-like

with

mat

te fi

nish

. Con

tain

two

size

s of

tiny

cry

stal

s.•

Can

use

on

outs

ide

of fo

od c

onta

iner

s bu

t not

insi

de.

• Pie

ce m

ust b

e st

ilted

; if y

ou w

ipe

off l

arge

cry

stal

s af

ter a

pplic

atio

n of

ea

ch c

oat p

iece

doe

s no

t nee

d to

be

stilt

ed.

Do

not s

tilt s

tone

war

e or

po

rcel

ain;

dry

foot

the

piec

e if

usin

g A

stro

Gem

s on

the

botto

m s

urfa

ce.

• C

an u

se M

othe

r of P

earl.

If u

sing

fire

d go

ld, a

pply

and

fire

cle

ar

glaz

e on

the

area

whe

re g

old

is d

esire

d.• P

orou

s su

rfac

e, u

se R

epel

lent

Sea

ler (

AC

-301

) for

wat

er-r

esis

tant

sur

face

36

Qui

ck R

efer

ence

Gui

de

Pro

duct

Hea

lth

Sta

tus

May

coF

irin

g R

ange

App

lied

By:

Gen

eral

N

otes

Boo

kA

pplic

atio

n

Ser

ies

2000

-G

loss

,S

pecs

tone

&S

tone

war

e-lik

eG

laze

s

Non

-tox

ic

Non

-mov

ing

whe

n fi

red.

Pg. 1

6Sh

elf

cone

06-

6.C

heck

Hig

h Fi

reG

uide

for

col

orch

ange

s at

she

lfco

ne 6

.

Shel

f co

ne 0

6-6.

Che

ck H

igh

Fire

Gui

de f

or c

olor

chan

ges

at s

helf

cone

6.

Bru

sh/S

pong

eA

pply

to p

rope

rlyfir

ed 0

4 bi

sque

.If

firin

g to

con

e 6

or h

ighe

r, ap

ply

to th

e cl

ay in

the

gree

nwar

e or

low

fired

bis

que-

04st

age.

App

ly to

pro

perly

fired

04

bisq

ue.

If fi

ring

to c

one

6or

hig

her,

appl

y to

the

clay

in th

egr

eenw

are

or lo

wfir

ed b

isqu

e-04

stag

e.

• App

ly 3

to 4

coa

ts.

• Int

erm

ixab

le• I

f doi

ng m

ajol

ica

tech

niqu

e w

ith m

atte

s, b

est t

o ap

ply

an a

dditi

onal

co

at. W

hen

hand

ling

you

wip

e of

f col

or.

• Ver

y im

porta

nt th

at b

isqu

e be

fire

d 2

cone

s ho

tter t

han

glaz

e fir

ing.

• Ser

ies

2000

Cle

ar g

laze

s an

d Sp

eckl

ed C

lear

gla

zes

shou

ld b

e ap

plie

d in

2 co

ats.

• If p

ittin

g oc

curs

, can

be

refir

ed o

ne c

one

cool

er th

an o

rigin

al fi

ring

for

smoo

th s

urfa

ce.

Ele

men

tsN

on-t

oxic

N

on-m

ovin

gw

hen

fire

d.

Pg. 1

4B

rush

/Spo

nge

Bru

sh/S

pong

e

• App

ly 3

-4 f

low

ing

coat

s.•

Inte

rmix

able

• T

he s

hape

of

the

obje

ct, a

pplic

atio

n, f

irin

g te

mpe

ratu

re, k

iln lo

ad

and

firi

ng ti

me

all a

ffec

t the

flo

w p

atte

rn.

• N

atur

al e

arth

tone

s.•

Surf

aces

var

y fr

om g

loss

to m

atte

.

GL

AZ

ES: N

ON

TO

XIC

Cla

ssic

Cra

ckle

sN

on-t

oxic

N

on-m

ovin

gw

hen

fire

d.

Pg. 1

2Sh

elf

cone

06-

6.C

heck

Hig

h Fi

reG

uide

for

col

orch

ange

s at

she

lfco

ne 6

.

App

ly to

pro

perly

fired

04

bisq

ue.

The

se g

laze

s ar

em

ore

fluid

at c

one

6; a

pply

two

coat

son

ly.

• App

ly 3

eve

n fl

owin

g co

ats.

• C

an w

ork

unde

r C

lass

ic C

rack

le u

sing

Str

oke

& C

oats

or

One

St

roke

s. I

f ap

plyi

ng m

ore

than

2 li

ght c

oats

this

tech

niqu

e w

ill

chan

ge th

e cr

acki

ng p

atte

rn.

• C

an w

ork

on to

p of

the

Cla

ssic

Cra

ckle

with

Str

oke

& C

oats

and

O

ne S

trok

e, b

ut te

st d

esig

n fi

rst a

s co

lor

will

fum

e.

• C

rack

s ne

ed to

be

stai

ned

afte

r fi

ring

for

cra

cks

to s

how

up.

Can

use

ink,

tran

sluc

ent s

tain

s, s

hoe

polis

h, e

tc.

Soft

Fan

Bru

shC

ryst

alit

esN

on-t

oxic

N

on-m

ovin

gw

hen

fire

d.

Pg. 1

3Sh

elf

cone

06-

6.C

heck

Hig

h Fi

reG

uide

for

col

orch

ange

s at

she

lfco

ne 6

.

App

ly to

pro

perly

fired

04

bisq

ue. I

ffir

ing

to c

one

6 or

high

er th

ese

glaz

esbe

com

e m

ore

fluid

.D

o no

t add

cry

stal

san

y cl

oser

than

1/2

”up

from

the

outs

ide

botto

m e

dge

of h

igh

fire

piec

es.

• App

ly 3

flo

win

g co

ats.

Fir

st c

oat-

sha

ke ja

r th

en a

pply

coa

t of

colo

r. S

econ

d co

at: s

hake

jar

and

appl

y co

at. T

hird

coa

t: st

ir th

e ja

ran

d sh

ake

befo

re a

pply

ing.

• C

ryst

alite

s do

not

flo

w, t

hey

just

spr

ead

or b

loom

out

.

37

Pro

duct

Hea

lth

Sta

tus

May

coF

irin

g R

ange

App

lied

By:

Gen

eral

N

otes

Boo

kA

pplic

atio

n

Stro

ke &

Coa

t®

Won

derg

laze

for

Bis

que

Non

-tox

ic

Non

-mov

ing

whe

n fi

red.

Pg. 1

1Sh

elf

cone

06-

6.So

me

colo

rs c

anho

ld to

she

lf c

one

9-10

. C

heck

Hig

hFi

re G

uide

for

colo

r ch

ange

s at

shel

f co

ne 6

.

Shel

f con

e 06

-6.

Som

e co

lors

can

hol

dto

she

lf co

ne 9

-10.

Che

ck H

igh

Fire

Gui

de fo

r cha

nges

at

shel

f con

e 6.

Bru

sh/S

pong

eA

pply

1 to

3 c

oats

to p

rope

rly

fire

d04

bis

que.

If f

irin

g to

con

e 6

or h

ighe

r ca

n be

appl

ied

to th

e cl

ayin

the

gree

nwar

eor

low

fir

edbi

sque

-04

stag

e.

App

ly to

pro

perly

fired

04

bisq

ue.

Sam

e as

St

roke

& C

oat®

• O

ne, t

wo

or th

ree

coat

s go

vern

s th

e fi

red

colo

r.•

Inte

rmix

able

• C

an u

se o

n to

p of

non

-mov

ing

glaz

es f

or M

ajol

ica.

• C

an b

e us

ed a

s an

ant

ique

und

er n

on-m

ovin

g gl

azes

.•

Prod

uct i

s a

glaz

e. C

an c

lear

gla

ze; i

f us

ing

3 co

ats

do n

ot n

eed

to

clea

r gl

aze.

• U

nfir

ed c

olor

is b

asic

ally

true

to th

e fi

red

resu

lts.

• C

olor

s ca

n be

laye

red

to b

uild

dep

th in

des

ign.

• Sh

iny

whe

n us

ed u

nder

a g

loss

gla

ze.

• Sh

iny

whe

n us

ed o

ver

a S-

2000

opa

que

glaz

e.•

Shin

y w

hen

used

in m

ultip

le c

oats

or

heav

ily o

ver

a m

atte

gla

ze.

• M

atte

whe

n ap

plie

d in

was

hes

or li

ght c

oats

ove

r m

atte

gla

zes.

Spec

kled

S

trok

e &

Coa

t®N

on-t

oxic

N

on-m

ovin

gw

hen

fire

d.

Pg. 1

1B

rush

/Spo

nge

• Sp

eckl

es h

ave

a va

riet

y of

spe

ck c

olor

s.• A

lso

corr

espo

nd w

ith a

Str

oke

& C

oat®

col

or.

• All

othe

r fe

atur

es s

ame

as S

trok

e &

Coa

t®

GL

AZ

ES: N

ON

TO

XIC

Dip

ping

S-2

000

Won

der

Cle

arD

ippi

ng

Non

-tox

ic

Din

nerw

are

Safe

Pg. 2

5Sh

elf

cone

06-

6.

App

ly to

pro

perly

fired

04

bisq

ue•

Lig

hten

s SC

-13

Gra

pel a

nd S

C-3

3 Fr

uit o

f th

e V

ine.

Dip

ping

SC

-209

Cle

arly

-the

-Bes

tD

ippi

ng

Non

-tox

ic

Din

nerw

are

Safe

Pg. 2

2Sh

elf

cone

06-

6.

App

ly to

pro

perly

fired

04

bisq

ue•

Dri

es f

aste

r, us

es le

ss p

rodu

ct.

• D

oes

not l

ight

en p

urpl

es o

f S

trok

e &

Coa

ts.

Qui

ck R

efer

ence

Gui

de

38

Qui

ck R

efer

ence

Gui

de

Pro

duct

Hea

lth

Sta

tus

May

coF

irin

g R

ange

App

lied

By:

Gen

eral

N

otes

Boo

kA

pplic

atio

n

Pot

tery

Coa

t

Pot

tery

Coa

tSt

ucco

Non

-tox

ic

Non

-mov

ing

whe

n fi

red

Non

-tox

ic

Non

-mov

ing

whe

n fi

red

Pg. 1

5Sh

elf

cone

06-

6.C

heck

Hig

h Fi

reG

uide

for

col

orch

ange

s at

she

lfco

ne 6

.

Shel

f co

ne 0

6-6.

Che

ck H

igh

Fire

Gui

de f

or c

olor

chan

ges

at s

helf

cone

6.

Shel

f con

e 06

-6.

Che

ck H

igh

Fire

Gui

de fo

r col

orch

ange

s at

she

lfco

ne 6

.

Soft

Fan

Bru

sh

Soft

Fan

Bru

sh

App

ly 3

eve

nco

ats

to p

rope

rly

fire

d 04

bis

que.

App

ly 3

eve

nco

ats

to p

rope

rly

fire

d 04

bis

que.

App

ly 1

-3 c

oats

topr

oper

ly fi

red

04bi

sque

. Do

not

appl

y be

low

the

halfw

ay p

oint

of

the

piec

e.

• Sh

ake

jar

wel

l bef

ore

appl

icat

ion.

• A

pply

coa

ts a

t rig

ht a

ngle

s to

min

imiz

e br

ush

mar

ks.

• To

use

on

a fu

nctio

nal i

tem

, suc

h as

din

nerw

are,

you

mus

t app

ly

clea

r gl

aze

to s

eal t

he s

urfa

ce.

• U

sed

alon

e, P

otte

ry C

oats

are

por

ous

and

not r

ecom

men

ded

for

use

with

din

nerw

are

or o

ther

fun

ctio

nal i

tem

s.

• N

ot o

verg

laze

com

patib

le.

• B

est l

ooks

are

ach

ieve

d w

hen

used

as

a ba

se c

oat i

n co

mbi

natio

nw

ith

Potte

ry C

asca

des

and

a fl

owin

g no

n-to

xic

glaz

e,su

ch a

s E

lem

ents

.

• St

ir Po

ttery

Coa

t Stu

cco

usin

g a

stir

stic

k. R

ecap

jar a

nd th

en s

hake

wel

l. ª A

fter

app

lyin

g th

ree

even

app

licat

ions

, che

ck th

e pi

ece

to m

ake

sure

the

text

ure

is e

venl

y di

stri

bute

d. A

pply

text

ure

in a

reas

that

may

hav

ebe

en le

ft b

are.

•

Use

d al

one,

Pot

tery

Coa

t Stu

ccos

are

por

ous

and

not r

ecom

men

ded

for

use

with

din

nerw

are

or o

ther

fun

ctio

nal i

tem

s.

• If

pie

ce is

to b

e pl

aced

on

furn

iture

, app

ly f

elt t

abs

to th

e bo

ttom

topr

otec

t fur

nitu

re f

rom

the

roug

h te

xtur

e of

the

glaz

e.

Pot

tery

Cas

cade

sN

on-t

oxic

M

oves

whe

nfi

red

Pg. 1

6B

rush

/Spo

nge/

Sque

eze

Bot

tle•

Can

be

appl

ied

over

, und

er a

nd in

bet

wee

n ot

her

glaz

es a

nd d

abbe

d on

at r

ando

m, e

venl

y or

une

venl

y to

cre

ate

diff

eren

t flo

w p

atte

rns.

•

Shou

ld b

e us

ed in

con

junc

tion

with

oth

er n

on-t

oxic

gla

zes

• C

lear

Cas

cade

mov

es m

ore

than

Whi

te, A

mbe

r an

d B

lack

Cas

cade

whe

n fi

red,

allo

win

g th

e co

lor

of th

e ba

se g

laze

to s

how

thro

ugh.

•

Shap

e of

the

piec

e af

fect

s th

e pe

rfor

man

ce o

f th

e gl

aze.

• O

verg

laze

com

patib

le.

GL

AZ

ES: N

ON

TO

XIC

39

Pro

duct

Hea

lth

Sta

tus

May

coF

irin

g R

ange

App

lied

By:

Gen

eral

N

otes

Boo

kA

pplic

atio

n

Art

Gla

zes

Food

safe

gla

zes

are

mar

ked

with

a st

ar *

sym

bol

Pg. 2

7Sh

elf

cone

06-

6C

heck

Hig

h Fi

reG

uide

for

col

orch

ange

s at

she

lfco

ne 6

Shel

f co

ne 0

6.W

ill n

ot h

igh

fire

con

e 6

orhi

gher

.

Bru

sh/S

pong

eA

pply

to p

rope

rly

fire

d 04

bis

que.

If f

irin

g to

con

e 6

or h

ighe

r, ap

ply

to th

e cl

ay in

the

gree

nwar

e or

low

fire

d bi

sque

-04

stag

e.

App

ly to

pro

perl

yfi

red

04 b

isqu

e.

• App

ly th

ree

full

flow

ing

coat

s un

less

not

ed d

iffer

ently

on

the

jar.

• G

laze

that

pro

duce

s lu

stro

us f

inis

hes,

dua

l col

orin

g, m

ulti

or s

ingl

e co

lore

d sp

ecs,

gol

d or

met

allic

fle

cks,

or

a gr

aine

d or

met

allic

look

is

cla

ssif

ied

as a

n A

rt G

laze

.•

Gre

at to

use

in g

laze

com

bina

tions

and

can

be

appl

ied

one,

two

or

thre

e co

ats.

• App

ly s

moo

thly

to p

lain

sur

face

s to

avo

id a

spo

tty f

inis

h.•

If a

pply

ing

to s

tone

war

e or

por

cela

in, m

ay n

eed

to th

in p

rodu

ct a

nd

appl

y le

ss c

olor

.

Bis

que

Gla

zes

Not

for

Foo

dIt

ems

Pg. 3

2B

rush

/Spo

nge

Bru

sh/S

pong

e

• App

ly f

our

full

flow

ing

coat

s, a

llow

ing

each

coa

t to

dry

betw

een

appl

icat

ions

.•

Mak

e su

re h

ands

and

bru

shes

are

cle

an.

• C

an in

term

ix th

ese

colo

rs e

xcep

t Im

peri

al Y

ello

w.

• N

eeds

mor

e ox

ygen

dur

ing

firi

ng to

dev

elop

.

GL

AZ

ES: L

EA

DE

D

Cle

ar A

rt G

laze

sN

ot f

or F

ood

Item

sPg

. 31

Shel

f co

ne 0

6-6

Che

ck H

igh

Fire

Gui

de f

or c

olor

chan

ges

at s

helf

cone

6.

App

ly to

pro

perly

fired

04

bisq

ue. I

ffir

ing

to c

one

6 or

high

er, a

pply

toth

e cl

ay in

the

gree

nwar

e or

low

fired

bis

que-

04

stag

e.

• G

laze

s in

this

ser

ies

are

not t

otal

ly c

lear

.•

Two

coat

s of

gla

ze a

re s

uffi

cien

t ove

r op

aque

und

ergl

azes

.•

If a

pplie

d to

o he

avily

may

cra

ze.

• If

app

lied

to a

n em

boss

ed p

iece

, col

or w

ill c

hang

e in

the

embo

ssed

ar

eas

due

to m

ore

colo

r in

thes

e ar

eas.

Bru

sh/S

pong

eE

xoti

c G

laze

sN

ot f

or F

ood

Item

sPg

. 33

Shel

f co

ne 0

6-6

Che

ck H

igh

Fire

Gui

de f

or c

olor

chan

ges

at s

helf

cone

6.

App

ly to

pro

perl

yfi

red

04 b

isqu

e.If

fir

ing

to c

one

6or

hig

her,

appl

yto

the

clay

in th

egr

eenw

are

or lo

wfi

red

bisq

ue-0

4st

age.

• T

he s

hape

of

the

piec

e, g

laze

app

licat

ion,

fir

ing

tem

pera

ture

and

ki

ln lo

ad a

ll af

fect

s th

e fi

nal s

urfa

ce.

• C

an b

e us

ed w

hen

doin

g gl

aze

com

bina

tions

to a

id in

the

flow

ing

patte

rn.

• App

ly th

ree

or m

ore

flow

ing

coat

s.•

Re-

firi

ng w

ill a

lso

brin

g ou

t mor

e of

a p

atte

rn c

hang

e.•

Som

e co

lors

hav

e a

com

bina

tion

of b

oth

mat

te a

nd g

loss

sur

face

s.

Qui

ck R

efer

ence

Gui

de

40

Pro

duct

Hea

lth

Sta

tus

May

coF

irin

g R

ange

App

lied

By:

Gen

eral

N

otes

Boo

kA

pplic

atio

n

Jung

le G

em™

Cry

stal

Gla

zes

Not

for

Foo

dIt

ems

Pg. 2

6Sh

elf

cone

06-

6C

heck

Hig

hFi

re G

uide

for

colo

r ch

ange

s at

shel

f co

ne 6

.

Shel

f co

ne 0

6-6

Che

ck H

igh

Fire

Gui

de f

or c

olor

chan

ges

at s

helf

cone

6.

Bru

sh/S

pong

eA

pply

to p

rope

rly

fire

d 04

bis

que.

If f

irin

g to

con

e 6

or h

ighe

r, ap

ply

to th

e cl

ay in

gree

nwar

e or

low

fire

d bi

sque

-04

stag

e

App

ly to

pro

perl

yfi

red

04 b

isqu

e.If

firi

ng to

con

e 6

orhi

gher

sho

uld

beap

plie

d to

the

clay

in g

reen

war

eor

low

fir

edbi

sque

-04

stag

e.

• M

ost c

ryst

al g

laze

s re

quir

e th

ree

coat

s.•

Avo

id a

larg

er c

once

ntra

tion

of c

ryst

al to

war

ds th

e bo

ttom

of

the

war

e.•

Do

not u

se o

n th

e in

side

of

food

con

tain

ers.

• If

doi

ng c

onta

iner

, ins

ide

colo

r sh

ould

be

a le

aded

gla

ze.

Rol

l-a-C

oat

Tin

tabl

e G

laze

C-2

10 N

on-T

oxic

C-1

10 F

ood

Safe

Pg. 1

8R

ollin

g

Dip

ping

• Tin

t Rol

l-a-C

oat w

ith S

troke

and

Coa

t or O

ne S

troke

s.•

Mea

sure

1-2

Tab

lesp

oons

of S

troke

and

Coa

t per

2 o

z of

Rol

l-a-C

oat.

• If

tint

ing

with

One

Stro

kes

use

1-2

Teas

poon

mea

sure

men

t.•

Pour

col

or in

, rol

l with

a c

ontin

uous

mot

ion

and

pour

col

or o

ut.

Plac

e w

are

upsi

de d

own

to d

rain

. W

hen

dry,

wip

e ex

cess

col

or.

GL

AZ

ES: L

EA

DE

D

C-1

00 C

lear

Dip

ping

Din

nerw

are

Safe

Pg. 2

5Sh

elf

cone

06-

6A

pply

to p

rope

rlyfir

ed 0

4 bi

sque

.•

Nee

ds to

be

mix

ed f

requ

ently

.•

Dip

in, s

hake

off

exc

ess

and

dry.

Dip

ping

C-1

01 B

lue

Whi

te C

lear

Dip

ping

Din

nerw

are

Safe

Pg. 2

5Sh

elf

cone

06-

6A

pply

topr

oper

ly f

ired

04

bisq

ue.

• T

his

prod

uct i

s th

e m

atch

to C

-101

bru

shin

g gl

aze.

• N

eeds

to b

e m

ixed

mor

e fr

eque

ntly

than

C-1

09.

• T

hinn

er th

an C

-109

Dip

ping

Dip

ping

C-1

09 W

onde

rC

lear

Dip

ping

Din

nerw

are

Safe

Pg. 2

5Sh

elf

cone

06-

6A

pply

topr

oper

ly f

ired

04

bisq

ue.

• V

ery

easy

to u

se.

• D

o no

t nee

d to

stir

fre

quen

tly.

• St

ir a

bout

eve

ry 1

5 to

20

min

utes

.•

Fast

er d

ryin

g tim

e

Qui

ck R

efer

ence

Gui

de

XC-16/E11/2004

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